Henry Spencer's POSIX.2 compatibile regular expression matching routines.

lib/libc/regex/Makefile

@@ -0,0 +1,121 @@
+# You probably want to take -DREDEBUG out of CFLAGS, and put something like
+# -O in, *after* testing (-DREDEBUG strengthens testing by enabling a lot of
+# internal assertion checking).  Take -Dconst= out for an ANSI compiler.
+# Do not take -DPOSIX_MISTAKE out.  REGCFLAGS isn't important to you (it's
+# for my use in some special contexts).
+#CFLAGS = -I. -Dconst= -DPOSIX_MISTAKE -DREDEBUG $(REGCFLAGS)
+CFLAGS = -I. -DPOSIX_MISTAKE -DREDEBUG $(REGCFLAGS)
+
+# If you have an ANSI compiler, take -o out of MKHFLAGS.  If you want
+# the Berkeley __P macro, put -b in.
+#MKHFLAGS = -o
+MKHFLAGS = -b
+
+LDFLAGS =
+
+# If you have an ANSI environment, take limits.h and stdlib.h out of
+# HMISSING and take memmove out of SRCMISSING and OBJMISSING.
+#HMISSING = limits.h stdlib.h
+#SRCMISSING = split.c memmove.c
+#OBJMISSING = split.o memmove.o
+HMISSING =
+SRCMISSING = split.c
+OBJMISSING = split.o
+H = cclass.h cname.h regex2.h utils.h $(HMISSING)
+REGSRC = regcomp.c regerror.c regexec.c regfree.c engine.c
+SRC = $(REGSRC) debug.c main.c $(SRCMISSING)
+
+# Internal stuff, should not need changing.
+OBJPRODN = regcomp.o regexec.o regerror.o regfree.o
+OBJS = $(OBJPRODN) debug.o main.o $(OBJMISSING)
+
+# Stuff that matters only if you're trying to lint the package.
+LINTFLAGS = -I. -Dstatic= -Dconst= -DREDEBUG
+LINTC = regcomp.c regexec.c regerror.c regfree.c debug.c main.c $(SRCMISSING)
+JUNKLINT =possible pointer alignment|null effect
+
+.SUFFIXES:	.ih .h
+.c.ih:
+	./mkh $(MKHFLAGS) -p $< >$@
+
+default:	r
+
+re:	$(OBJS)
+	$(CC) $(CFLAGS) $(LDFLAGS) $(OBJS) -o $@
+
+o:	$(OBJPRODN)
+
+REGEXHSRC = regex2.h reg*.c
+h:	$(REGEXHSRC)
+	./mkh $(MKHFLAGS) -i _REGEX_H_ $(REGEXHSRC) >regex.tmp
+	cmp -s regex.tmp regex.h 2>/dev/null || cp regex.tmp regex.h
+	rm -f regex.tmp
+
+regcomp.o regexec.o regfree.o debug.o:	utils.h regex.h regex2.h
+regcomp.o:	cclass.h cname.h regcomp.ih
+regexec.o:	engine.c engine.ih
+regerror.o:	regerror.ih
+regerror.o:	utils.h
+debug.o:	debug.ih
+main.o:	main.ih
+
+r:	re tests
+	./re <tests
+	./re -el <tests
+	./re -er <tests
+
+ra:	./re tests
+	-./re <tests
+	-./re -el <tests
+	-./re -er <tests
+
+rx:	./re tests
+	./re -x <tests
+	./re -x -el <tests
+	./re -x -er <tests
+
+t:	./re tests
+	-time ./re <tests
+	-time ./re -cs <tests
+	-time ./re -el <tests
+	-time ./re -cs -el <tests
+
+e:	echeck re tests
+	./re -d <tests | awk -f echeck
+
+l:	$(LINTC)
+	lint $(LINTFLAGS) -h $(LINTC) 2>&1 | egrep -v '$(JUNKLINT)' | tee lint
+
+fullprint:
+	ti README WHATSNEW notes todo | hplist
+	ti *.h | hplist
+	hplist *.c
+	hplist regex.3 regex.7
+
+print:
+	ti README WHATSNEW notes todo | hplist
+	ti *.h | hplist
+	hplist reg*.c engine.c
+
+clean:	tidy
+	rm -f *.o *.s *.ih re
+
+tidy:
+	rm -f junk* core dtr regex.tmp lint
+
+spotless:	clean
+	rm -f mkh regex.h
+
+mkh:	/usr/henry/bin/mkh
+	cp $? $@
+
+DTRH = cclass.h cname.h regex2.h utils.h limits.h stdlib.h
+DTR = README WHATSNEW Makefile Makefile.44bsd mkh regex.3 regex.7 tests $(DTRH) $(SRC)
+dtr:	$(DTR)
+	makedtr $(DTR) >$@
+
+cio:	$(DTR)
+	cio $(DTR)
+
+rdf:	$(DTR)
+	rcsdiff -c $(DTR)

lib/libc/regex/Makefile.inc

@@ -0,0 +1,14 @@
+# actually this is a Makefile.inc
+
+# regex sources
+.PATH: ${.CURDIR}/regex
+
+CFLAGS+=-DPOSIX_MISTAKE
+
+SRCS+=	regcomp.c regerror.c regexec.c regfree.c
+
+MAN3+=	regex.0
+MAN7+=	re_format.0
+
+MLINKS+=regex.3 regcomp.3 regex.3 regexec.3 regex.3 regerror.3
+MLINKS+=regexec.3 regfree.3

lib/libc/regex/README

@@ -0,0 +1,29 @@
+alpha3.1 release.
+Sat Aug 14 01:38:38 EDT 1993
+henry@zoo.toronto.edu
+
+See WHATSNEW for change listing.
+
+installation notes:
+--------
+Read the comments at the beginning of Makefile before running.
+
+Utils.h contains some things that just might have to be modified on
+some systems, as well as a nested include (ugh) of <assert.h>.
+
+Split.c is used for regression testing but is not part of the RE routines
+themselves.
+
+"make h" builds regex.h, which is needed for everything else.  You may need
+to "chmod +x mkh" first.
+
+After that, just "make" will build regcomp.o, regexec.o, regfree.o,
+and regerror.o (the actual routines), bundle them together into a test
+program, and run regression tests on them.  No output is good output.
+
+"make o" builds just the .o files for the actual routines (e.g. when
+you're happy with testing, have adjusted CFLAGS for production compile,
+have done "make clean", and want to build just the library .o files).
+
+Regex.h goes in /usr/include.  All other .h files are internal only.
+--------

lib/libc/regex/WHATSNEW

@@ -0,0 +1,60 @@
+New in alpha3.1:  Basically nothing, this release is just a bookkeeping
+convenience.  Stay tuned.
+
+New in alpha3.0:  Performance is no better, alas, but some fixes have been
+made and some functionality has been added.  (This is basically the "get
+it out the door in time for 4.4" release.)  One bug fix:  regfree() didn't
+free the main internal structure (how embarrassing).  It is now possible
+to put NULs in either the RE or the target string, using (resp.) a new
+REG_PEND flag and the old REG_STARTEND flag.  The REG_NOSPEC flag to
+regcomp() makes all characters ordinary, so you can match a literal
+string easily (this will become more useful when performance improves!).
+There are now primitives to match beginnings and ends of words, although
+the syntax is disgusting and so is the implementation.  The REG_ATOI
+debugging interface has changed a bit.  And there has been considerable
+internal cleanup of various kinds.
+
+New in alpha2.3:  Split change list out of README, and moved flags notes
+into Makefile.  Macro-ized the name of regex(7) in regex(3), since it has
+to change for 4.4BSD.  Cleanup work in engine.c, and some new regression
+tests to catch tricky cases thereof.
+
+New in alpha2.2:  Out-of-date manpages updated.  Regerror() acquires two
+small extensions -- REG_ITOA and REG_ATOI -- which avoid debugging kludges
+in my own test program and might be useful to others for similar purposes.
+The regression test will now compile (and run) without REDEBUG.  The
+BRE \$ bug is fixed.  Most uses of "uchar" are gone; it's all chars now.
+Char/uchar parameters are now written int/unsigned, to avoid possible
+portability problems with unpromoted parameters.  Some unsigned casts have
+been introduced to minimize portability problems with shifting into sign
+bits.
+
+New in alpha2.1:  Lots of little stuff, cleanup and fixes.  The one big
+thing is that regex.h is now generated, using mkh, rather than being
+supplied in the distribution; due to circularities in dependencies,
+you have to build regex.h explicitly by "make h".  The two known bugs
+have been fixed (and the regression test now checks for them), as has a
+problem with assertions not being suppressed in the absence of REDEBUG.
+No performance work yet.
+
+New in alpha2:  Backslash-anything is an ordinary character, not an
+error (except, of course, for the handful of backslashed metacharacters
+in BREs), which should reduce script breakage.  The regression test
+checks *where* null strings are supposed to match, and has generally
+been tightened up somewhat.  Small bug fixes in parameter passing (not
+harmful, but technically errors) and some other areas.  Debugging
+invoked by defining REDEBUG rather than not defining NDEBUG.
+
+New in alpha+3:  full prototyping for internal routines, using a little
+helper program, mkh, which extracts prototypes given in stylized comments.
+More minor cleanup.  Buglet fix:  it's CHAR_BIT, not CHAR_BITS.  Simple
+pre-screening of input when a literal string is known to be part of the
+RE; this does wonders for performance.
+
+New in alpha+2:  minor bits of cleanup.  Notably, the number "32" for the
+word width isn't hardwired into regexec.c any more, the public header
+file prototypes the functions if __STDC__ is defined, and some small typos
+in the manpages have been fixed.
+
+New in alpha+1:  improvements to the manual pages, and an important
+extension, the REG_STARTEND option to regexec().

lib/libc/regex/cclass.h

@@ -0,0 +1,31 @@
+/* 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,		""
+};

lib/libc/regex/cname.h

@@ -0,0 +1,102 @@
+/* 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,
+};

lib/libc/regex/debug.c

@@ -0,0 +1,242 @@
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <regex.h>
+
+#include "utils.h"
+#include "regex2.h"
+#include "debug.ih"
+
+/*
+ - regprint - print a regexp for debugging
+ == void regprint(regex_t *r, FILE *d);
+ */
+void
+regprint(r, d)
+regex_t *r;
+FILE *d;
+{
+	register struct re_guts *g = r->re_g;
+	register int i;
+	register int c;
+	register int last;
+	int nincat[NC];
+
+	fprintf(d, "%ld states, %d categories", (long)g->nstates,
+							g->ncategories);
+	fprintf(d, ", first %ld last %ld", (long)g->firststate,
+						(long)g->laststate);
+	if (g->iflags&USEBOL)
+		fprintf(d, ", USEBOL");
+	if (g->iflags&USEEOL)
+		fprintf(d, ", USEEOL");
+	if (g->iflags&BAD)
+		fprintf(d, ", BAD");
+	if (g->nsub > 0)
+		fprintf(d, ", nsub=%ld", (long)g->nsub);
+	if (g->must != NULL)
+		fprintf(d, ", must(%ld) `%*s'", (long)g->mlen, (int)g->mlen,
+								g->must);
+	if (g->backrefs)
+		fprintf(d, ", backrefs");
+	if (g->nplus > 0)
+		fprintf(d, ", nplus %ld", (long)g->nplus);
+	fprintf(d, "\n");
+	s_print(g, d);
+	for (i = 0; i < g->ncategories; i++) {
+		nincat[i] = 0;
+		for (c = CHAR_MIN; c <= CHAR_MAX; c++)
+			if (g->categories[c] == i)
+				nincat[i]++;
+	}
+	fprintf(d, "cc0#%d", nincat[0]);
+	for (i = 1; i < g->ncategories; i++)
+		if (nincat[i] == 1) {
+			for (c = CHAR_MIN; c <= CHAR_MAX; c++)
+				if (g->categories[c] == i)
+					break;
+			fprintf(d, ", %d=%s", i, regchar(c));
+		}
+	fprintf(d, "\n");
+	for (i = 1; i < g->ncategories; i++)
+		if (nincat[i] != 1) {
+			fprintf(d, "cc%d\t", i);
+			last = -1;
+			for (c = CHAR_MIN; c <= CHAR_MAX+1; c++)	/* +1 does flush */
+				if (c <= CHAR_MAX && g->categories[c] == i) {
+					if (last < 0) {
+						fprintf(d, "%s", regchar(c));
+						last = c;
+					}
+				} else {
+					if (last >= 0) {
+						if (last != c-1)
+							fprintf(d, "-%s",
+								regchar(c-1));
+						last = -1;
+					}
+				}
+			fprintf(d, "\n");
+		}
+}
+
+/*
+ - s_print - print the strip for debugging
+ == static void s_print(register struct re_guts *g, FILE *d);
+ */
+static void
+s_print(g, d)
+register struct re_guts *g;
+FILE *d;
+{
+	register sop *s;
+	register cset *cs;
+	register int i;
+	register int done = 0;
+	register sop opnd;
+	register int col = 0;
+	register int last;
+	register sopno offset = 2;
+#	define	GAP()	{	if (offset % 5 == 0) { \
+					if (col > 40) { \
+						fprintf(d, "\n\t"); \
+						col = 0; \
+					} else { \
+						fprintf(d, " "); \
+						col++; \
+					} \
+				} else \
+					col++; \
+				offset++; \
+			}
+
+	if (OP(g->strip[0]) != OEND)
+		fprintf(d, "missing initial OEND!\n");
+	for (s = &g->strip[1]; !done; s++) {
+		opnd = OPND(*s);
+		switch (OP(*s)) {
+		case OEND:
+			fprintf(d, "\n");
+			done = 1;
+			break;
+		case OCHAR:
+			if (strchr("\\|()^$.[+*?{}!<> ", (char)opnd) != NULL)
+				fprintf(d, "\\%c", (char)opnd);
+			else
+				fprintf(d, "%s", regchar((char)opnd));
+			break;
+		case OBOL:
+			fprintf(d, "^");
+			break;
+		case OEOL:
+			fprintf(d, "$");
+			break;
+		case OBOW:
+			fprintf(d, "\\{");
+			break;
+		case OEOW:
+			fprintf(d, "\\}");
+			break;
+		case OANY:
+			fprintf(d, ".");
+			break;
+		case OANYOF:
+			fprintf(d, "[(%ld)", (long)opnd);
+			cs = &g->sets[opnd];
+			last = -1;
+			for (i = 0; i < g->csetsize+1; i++)	/* +1 flushes */
+				if (CHIN(cs, i) && i < g->csetsize) {
+					if (last < 0) {
+						fprintf(d, "%s", regchar(i));
+						last = i;
+					}
+				} else {
+					if (last >= 0) {
+						if (last != i-1)
+							fprintf(d, "-%s",
+								regchar(i-1));
+						last = -1;
+					}
+				}
+			fprintf(d, "]");
+			break;
+		case OBACK_:
+			fprintf(d, "(\\<%ld>", (long)opnd);
+			break;
+		case O_BACK:
+			fprintf(d, "<%ld>\\)", (long)opnd);
+			break;
+		case OPLUS_:
+			fprintf(d, "(+");
+			if (OP(*(s+opnd)) != O_PLUS)
+				fprintf(d, "<%ld>", (long)opnd);
+			break;
+		case O_PLUS:
+			if (OP(*(s-opnd)) != OPLUS_)
+				fprintf(d, "<%ld>", (long)opnd);
+			fprintf(d, "+)");
+			break;
+		case OQUEST_:
+			fprintf(d, "(?");
+			if (OP(*(s+opnd)) != O_QUEST)
+				fprintf(d, "<%ld>", (long)opnd);
+			break;
+		case O_QUEST:
+			if (OP(*(s-opnd)) != OQUEST_)
+				fprintf(d, "<%ld>", (long)opnd);
+			fprintf(d, "?)");
+			break;
+		case OLPAREN:
+			fprintf(d, "((<%ld>", (long)opnd);
+			break;
+		case ORPAREN:
+			fprintf(d, "<%ld>))", (long)opnd);
+			break;
+		case OCH_:
+			fprintf(d, "<");
+			if (OP(*(s+opnd)) != OOR2)
+				fprintf(d, "<%ld>", (long)opnd);
+			break;
+		case OOR1:
+			if (OP(*(s-opnd)) != OOR1 && OP(*(s-opnd)) != OCH_)
+				fprintf(d, "<%ld>", (long)opnd);
+			fprintf(d, "|");
+			break;
+		case OOR2:
+			fprintf(d, "|");
+			if (OP(*(s+opnd)) != OOR2 && OP(*(s+opnd)) != O_CH)
+				fprintf(d, "<%ld>", (long)opnd);
+			break;
+		case O_CH:
+			if (OP(*(s-opnd)) != OOR1)
+				fprintf(d, "<%ld>", (long)opnd);
+			fprintf(d, ">");
+			break;
+		default:
+			fprintf(d, "!%d(%d)!", OP(*s), opnd);
+			break;
+		}
+		if (!done)
+			GAP();
+	}
+}
+
+/*
+ - regchar - make a character printable
+ == static char *regchar(int ch);
+ */
+static char *			/* -> representation */
+regchar(ch)
+int ch;
+{
+	static char buf[10];
+
+	if (isprint(ch) || ch == ' ')
+		sprintf(buf, "%c", ch);
+	else
+		sprintf(buf, "\\%o", ch);
+	return(buf);
+}

lib/libc/regex/debug.ih

@@ -0,0 +1,14 @@
+/* ========= begin header generated by ./mkh ========= */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* === debug.c === */
+void regprint __P((regex_t *r, FILE *d));
+static void s_print __P((register struct re_guts *g, FILE *d));
+static char *regchar __P((int ch));
+
+#ifdef __cplusplus
+}
+#endif
+/* ========= end header generated by ./mkh ========= */

lib/libc/regex/engine.ih

@@ -0,0 +1,35 @@
+/* ========= begin header generated by ./mkh ========= */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* === engine.c === */
+static int matcher __P((register struct re_guts *g, char *string, size_t nmatch, regmatch_t pmatch[], int eflags));
+static char *dissect __P((register struct match *m, char *start, char *stop, sopno startst, sopno stopst));
+static char *backref __P((register struct match *m, char *start, char *stop, sopno startst, sopno stopst, sopno lev));
+static char *fast __P((register struct match *m, char *start, char *stop, sopno startst, sopno stopst));
+static char *slow __P((register struct match *m, char *start, char *stop, sopno startst, sopno stopst));
+static states step __P((register struct re_guts *g, int start, int stop, register states bef, int ch, register states aft));
+#define	BOL	(OUT+1)
+#define	EOL	(BOL+1)
+#define	BOLEOL	(BOL+2)
+#define	NOTHING	(BOL+3)
+#define	BOW	(BOL+4)
+#define	EOW	(BOL+5)
+#define	CODEMAX	(BOL+5)		/* highest code used */
+#define	NONCHAR(c)	((c) > CHAR_MAX)
+#define	NNONCHAR	(CODEMAX-CHAR_MAX)
+#ifdef REDEBUG
+static void print __P((struct match *m, char *caption, states st, int ch, FILE *d));
+#endif
+#ifdef REDEBUG
+static void at __P((struct match *m, char *title, char *start, char *stop, sopno startst, sopno stopst));
+#endif
+#ifdef REDEBUG
+static char *pchar __P((int ch));
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+/* ========= end header generated by ./mkh ========= */

lib/libc/regex/limits.h

@@ -0,0 +1,4 @@
+#define	_POSIX2_RE_DUP_MAX	255
+#define	CHAR_MIN	(-128)
+#define	CHAR_MAX	127
+#define	CHAR_BIT	8

lib/libc/regex/main.c

@@ -0,0 +1,510 @@
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <regex.h>
+#include <assert.h>
+
+#include "main.ih"
+
+char *progname;
+int debug = 0;
+int line = 0;
+int status = 0;
+
+int copts = REG_EXTENDED;
+int eopts = 0;
+regoff_t startoff = 0;
+regoff_t endoff = 0;
+
+
+extern int split();
+extern void regprint();
+
+/*
+ - main - do the simple case, hand off to regress() for regression
+ */
+main(argc, argv)
+int argc;
+char *argv[];
+{
+	regex_t re;
+#	define	NS	10
+	regmatch_t subs[NS];
+	char erbuf[100];
+	int err;
+	size_t len;
+	int c;
+	int errflg = 0;
+	register int i;
+	extern int optind;
+	extern char *optarg;
+
+	progname = argv[0];
+
+	while ((c = getopt(argc, argv, "c:e:S:E:x")) != EOF)
+		switch (c) {
+		case 'c':	/* compile options */
+			copts = options('c', optarg);
+			break;
+		case 'e':	/* execute options */
+			eopts = options('e', optarg);
+			break;
+		case 'S':	/* start offset */
+			startoff = (regoff_t)atoi(optarg);
+			break;
+		case 'E':	/* end offset */
+			endoff = (regoff_t)atoi(optarg);
+			break;
+		case 'x':	/* Debugging. */
+			debug++;
+			break;
+		case '?':
+		default:
+			errflg++;
+			break;
+		}
+	if (errflg) {
+		fprintf(stderr, "usage: %s ", progname);
+		fprintf(stderr, "[-c copt][-C][-d] [re]\n");
+		exit(2);
+	}
+
+	if (optind >= argc) {
+		regress(stdin);
+		exit(status);
+	}
+
+	err = regcomp(&re, argv[optind++], copts);
+	if (err) {
+		len = regerror(err, &re, erbuf, sizeof(erbuf));
+		fprintf(stderr, "error %s, %d/%d `%s'\n",
+			eprint(err), len, sizeof(erbuf), erbuf);
+		exit(status);
+	}
+	regprint(&re, stdout);	
+
+	if (optind >= argc) {
+		regfree(&re);
+		exit(status);
+	}
+
+	if (eopts&REG_STARTEND) {
+		subs[0].rm_so = startoff;
+		subs[0].rm_eo = strlen(argv[optind]) - endoff;
+	}
+	err = regexec(&re, argv[optind], (size_t)NS, subs, eopts);
+	if (err) {
+		len = regerror(err, &re, erbuf, sizeof(erbuf));
+		fprintf(stderr, "error %s, %d/%d `%s'\n",
+			eprint(err), len, sizeof(erbuf), erbuf);
+		exit(status);
+	}
+	if (!(copts&REG_NOSUB)) {
+		len = (int)(subs[0].rm_eo - subs[0].rm_so);
+		if (subs[0].rm_so != -1) {
+			if (len != 0)
+				printf("match `%.*s'\n", len,
+					argv[optind] + subs[0].rm_so);
+			else
+				printf("match `'@%.1s\n",
+					argv[optind] + subs[0].rm_so);
+		}
+		for (i = 1; i < NS; i++)
+			if (subs[i].rm_so != -1)
+				printf("(%d) `%.*s'\n", i,
+					(int)(subs[i].rm_eo - subs[i].rm_so),
+					argv[optind] + subs[i].rm_so);
+	}
+	exit(status);
+}
+
+/*
+ - regress - main loop of regression test
+ == void regress(FILE *in);
+ */
+void
+regress(in)
+FILE *in;
+{
+	char inbuf[1000];
+#	define	MAXF	10
+	char *f[MAXF];
+	int nf;
+	int i;
+	char erbuf[100];
+	size_t ne;
+	char *badpat = "invalid regular expression";
+#	define	SHORT	10
+	char *bpname = "REG_BADPAT";
+	regex_t re;
+
+	while (fgets(inbuf, sizeof(inbuf), in) != NULL) {
+		line++;
+		if (inbuf[0] == '#' || inbuf[0] == '\n')
+			continue;			/* NOTE CONTINUE */
+		inbuf[strlen(inbuf)-1] = '\0';	/* get rid of stupid \n */
+		if (debug)
+			fprintf(stdout, "%d:\n", line);
+		nf = split(inbuf, f, MAXF, "\t\t");
+		if (nf < 3) {
+			fprintf(stderr, "bad input, line %d\n", line);
+			exit(1);
+		}
+		for (i = 0; i < nf; i++)
+			if (strcmp(f[i], "\"\"") == 0)
+				f[i] = "";
+		if (nf <= 3)
+			f[3] = NULL;
+		if (nf <= 4)
+			f[4] = NULL;
+		try(f[0], f[1], f[2], f[3], f[4], options('c', f[1]));
+		if (opt('&', f[1]))	/* try with either type of RE */
+			try(f[0], f[1], f[2], f[3], f[4],
+					options('c', f[1]) &~ REG_EXTENDED);
+	}
+
+	ne = regerror(REG_BADPAT, (regex_t *)NULL, erbuf, sizeof(erbuf));
+	if (strcmp(erbuf, badpat) != 0 || ne != strlen(badpat)+1) {
+		fprintf(stderr, "end: regerror() test gave `%s' not `%s'\n",
+							erbuf, badpat);
+		status = 1;
+	}
+	ne = regerror(REG_BADPAT, (regex_t *)NULL, erbuf, (size_t)SHORT);
+	if (strncmp(erbuf, badpat, SHORT-1) != 0 || erbuf[SHORT-1] != '\0' ||
+						ne != strlen(badpat)+1) {
+		fprintf(stderr, "end: regerror() short test gave `%s' not `%.*s'\n",
+						erbuf, SHORT-1, badpat);
+		status = 1;
+	}
+	ne = regerror(REG_ITOA|REG_BADPAT, (regex_t *)NULL, erbuf, sizeof(erbuf));
+	if (strcmp(erbuf, bpname) != 0 || ne != strlen(bpname)+1) {
+		fprintf(stderr, "end: regerror() ITOA test gave `%s' not `%s'\n",
+						erbuf, bpname);
+		status = 1;
+	}
+	re.re_endp = bpname;
+	ne = regerror(REG_ATOI, &re, erbuf, sizeof(erbuf));
+	if (atoi(erbuf) != (int)REG_BADPAT) {
+		fprintf(stderr, "end: regerror() ATOI test gave `%s' not `%ld'\n",
+						erbuf, (long)REG_BADPAT);
+		status = 1;
+	} else if (ne != strlen(erbuf)+1) {
+		fprintf(stderr, "end: regerror() ATOI test len(`%s') = %ld\n",
+						erbuf, (long)REG_BADPAT);
+		status = 1;
+	}
+}
+
+/*
+ - try - try it, and report on problems
+ == void try(char *f0, char *f1, char *f2, char *f3, char *f4, int opts);
+ */
+void
+try(f0, f1, f2, f3, f4, opts)
+char *f0;
+char *f1;
+char *f2;
+char *f3;
+char *f4;
+int opts;			/* may not match f1 */
+{
+	regex_t re;
+#	define	NSUBS	10
+	regmatch_t subs[NSUBS];
+#	define	NSHOULD	15
+	char *should[NSHOULD];
+	int nshould;
+	char erbuf[100];
+	int err;
+	int len;
+	char *type = (opts & REG_EXTENDED) ? "ERE" : "BRE";
+	register int i;
+	char *grump;
+	char f0copy[1000];
+	char f2copy[1000];
+
+	strcpy(f0copy, f0);
+	re.re_endp = (opts&REG_PEND) ? f0copy + strlen(f0copy) : NULL;
+	fixstr(f0copy);
+	err = regcomp(&re, f0copy, opts);
+	if (err != 0 && (!opt('C', f1) || err != efind(f2))) {
+		/* unexpected error or wrong error */
+		len = regerror(err, &re, erbuf, sizeof(erbuf));
+		fprintf(stderr, "%d: %s error %s, %d/%d `%s'\n",
+					line, type, eprint(err), len,
+					sizeof(erbuf), erbuf);
+		status = 1;
+	} else if (err == 0 && opt('C', f1)) {
+		/* unexpected success */
+		fprintf(stderr, "%d: %s should have given REG_%s\n",
+						line, type, f2);
+		status = 1;
+		err = 1;	/* so we won't try regexec */
+	}
+
+	if (err != 0) {
+		regfree(&re);
+		return;
+	}
+
+	strcpy(f2copy, f2);
+	fixstr(f2copy);
+
+	if (options('e', f1)&REG_STARTEND) {
+		if (strchr(f2, '(') == NULL || strchr(f2, ')') == NULL)
+			fprintf(stderr, "%d: bad STARTEND syntax\n", line);
+		subs[0].rm_so = strchr(f2, '(') - f2 + 1;
+		subs[0].rm_eo = strchr(f2, ')') - f2;
+	}
+	err = regexec(&re, f2copy, NSUBS, subs, options('e', f1));
+
+	if (err != 0 && (f3 != NULL || err != REG_NOMATCH)) {
+		/* unexpected error or wrong error */
+		len = regerror(err, &re, erbuf, sizeof(erbuf));
+		fprintf(stderr, "%d: %s exec error %s, %d/%d `%s'\n",
+					line, type, eprint(err), len,
+					sizeof(erbuf), erbuf);
+		status = 1;
+	} else if (err != 0) {
+		/* nothing more to check */
+	} else if (f3 == NULL) {
+		/* unexpected success */
+		fprintf(stderr, "%d: %s exec should have failed\n",
+						line, type);
+		status = 1;
+		err = 1;		/* just on principle */
+	} else if (opts&REG_NOSUB) {
+		/* nothing more to check */
+	} else if ((grump = check(f2, subs[0], f3)) != NULL) {
+		fprintf(stderr, "%d: %s %s\n", line, type, grump);
+		status = 1;
+		err = 1;
+	}
+
+	if (err != 0 || f4 == NULL) {
+		regfree(&re);
+		return;
+	}
+
+	for (i = 1; i < NSHOULD; i++)
+		should[i] = NULL;
+	nshould = split(f4, should+1, NSHOULD-1, ",");
+	if (nshould == 0) {
+		nshould = 1;
+		should[1] = "";
+	}
+	for (i = 1; i < NSUBS; i++) {
+		grump = check(f2, subs[i], should[i]);
+		if (grump != NULL) {
+			fprintf(stderr, "%d: %s $%d %s\n", line,
+							type, i, grump);
+			status = 1;
+			err = 1;
+		}
+	}
+
+	regfree(&re);
+}
+
+/*
+ - options - pick options out of a regression-test string
+ == int options(int type, char *s);
+ */
+int
+options(type, s)
+int type;			/* 'c' compile, 'e' exec */
+char *s;
+{
+	register char *p;
+	register int o = (type == 'c') ? copts : eopts;
+	register char *legal = (type == 'c') ? "bisnmp" : "^$#tl";
+
+	for (p = s; *p != '\0'; p++)
+		if (strchr(legal, *p) != NULL)
+			switch (*p) {
+			case 'b':
+				o &= ~REG_EXTENDED;
+				break;
+			case 'i':
+				o |= REG_ICASE;
+				break;
+			case 's':
+				o |= REG_NOSUB;
+				break;
+			case 'n':
+				o |= REG_NEWLINE;
+				break;
+			case 'm':
+				o &= ~REG_EXTENDED;
+				o |= REG_NOSPEC;
+				break;
+			case 'p':
+				o |= REG_PEND;
+				break;
+			case '^':
+				o |= REG_NOTBOL;
+				break;
+			case '$':
+				o |= REG_NOTEOL;
+				break;
+			case '#':
+				o |= REG_STARTEND;
+				break;
+			case 't':	/* trace */
+				o |= REG_TRACE;
+				break;
+			case 'l':	/* force long representation */
+				o |= REG_LARGE;
+				break;
+			case 'r':	/* force backref use */
+				o |= REG_BACKR;
+				break;
+			}
+	return(o);
+}
+
+/*
+ - opt - is a particular option in a regression string?
+ == int opt(int c, char *s);
+ */
+int				/* predicate */
+opt(c, s)
+int c;
+char *s;
+{
+	return(strchr(s, c) != NULL);
+}
+
+/*
+ - fixstr - transform magic characters in strings
+ == void fixstr(register char *p);
+ */
+void
+fixstr(p)
+register char *p;
+{
+	if (p == NULL)
+		return;
+
+	for (; *p != '\0'; p++)
+		if (*p == 'N')
+			*p = '\n';
+		else if (*p == 'T')
+			*p = '\t';
+		else if (*p == 'S')
+			*p = ' ';
+		else if (*p == 'Z')
+			*p = '\0';
+}
+
+/*
+ - check - check a substring match
+ == char *check(char *str, regmatch_t sub, char *should);
+ */
+char *				/* NULL or complaint */
+check(str, sub, should)
+char *str;
+regmatch_t sub;
+char *should;
+{
+	register int len;
+	register int shlen;
+	register char *p;
+	static char grump[500];
+	register char *at = NULL;
+
+	if (should != NULL && strcmp(should, "-") == 0)
+		should = NULL;
+	if (should != NULL && should[0] == '@') {
+		at = should + 1;
+		should = "";
+	}
+
+	/* check rm_so and rm_eo for consistency */
+	if (sub.rm_so > sub.rm_eo || (sub.rm_so == -1 && sub.rm_eo != -1) ||
+				(sub.rm_so != -1 && sub.rm_eo == -1) ||
+				(sub.rm_so != -1 && sub.rm_so < 0) ||
+				(sub.rm_eo != -1 && sub.rm_eo < 0) ) {
+		sprintf(grump, "start %ld end %ld", (long)sub.rm_so,
+							(long)sub.rm_eo);
+		return(grump);
+	}
+
+	/* check for no match */
+	if (sub.rm_so == -1 && should == NULL)
+		return(NULL);
+	if (sub.rm_so == -1)
+		return("did not match");
+
+	/* check for in range */
+	if (sub.rm_eo > strlen(str)) {
+		sprintf(grump, "start %ld end %ld, past end of string",
+					(long)sub.rm_so, (long)sub.rm_eo);
+		return(grump);
+	}
+
+	len = (int)(sub.rm_eo - sub.rm_so);
+	shlen = (int)strlen(should);
+	p = str + sub.rm_so;
+
+	/* check for not supposed to match */
+	if (should == NULL) {
+		sprintf(grump, "matched `%.*s'", len, p);
+		return(grump);
+	}
+
+	/* check for wrong match */
+	if (len != shlen || strncmp(p, should, (size_t)shlen) != 0) {
+		sprintf(grump, "matched `%.*s' instead", len, p);
+		return(grump);
+	}
+	if (shlen > 0)
+		return(NULL);
+
+	/* check null match in right place */
+	if (at == NULL)
+		return(NULL);
+	shlen = strlen(at);
+	if (shlen == 0)
+		shlen = 1;	/* force check for end-of-string */
+	if (strncmp(p, at, shlen) != 0) {
+		sprintf(grump, "matched null at `%.20s'", p);
+		return(grump);
+	}
+	return(NULL);
+}
+
+/*
+ - eprint - convert error number to name
+ == static char *eprint(int err);
+ */
+static char *
+eprint(err)
+int err;
+{
+	static char epbuf[100];
+	size_t len;
+
+	len = regerror(REG_ITOA|err, (regex_t *)NULL, epbuf, sizeof(epbuf));
+	assert(len <= sizeof(epbuf));
+	return(epbuf);
+}
+
+/*
+ - efind - convert error name to number
+ == static int efind(char *name);
+ */
+static int
+efind(name)
+char *name;
+{
+	static char efbuf[100];
+	size_t n;
+	regex_t re;
+
+	sprintf(efbuf, "REG_%s", name);
+	assert(strlen(efbuf) < sizeof(efbuf));
+	re.re_endp = efbuf;
+	(void) regerror(REG_ATOI, &re, efbuf, sizeof(efbuf));
+	return(atoi(efbuf));
+}

lib/libc/regex/main.ih

@@ -0,0 +1,19 @@
+/* ========= begin header generated by ./mkh ========= */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* === main.c === */
+void regress __P((FILE *in));
+void try __P((char *f0, char *f1, char *f2, char *f3, char *f4, int opts));
+int options __P((int type, char *s));
+int opt __P((int c, char *s));
+void fixstr __P((register char *p));
+char *check __P((char *str, regmatch_t sub, char *should));
+static char *eprint __P((int err));
+static int efind __P((char *name));
+
+#ifdef __cplusplus
+}
+#endif
+/* ========= end header generated by ./mkh ========= */

lib/libc/regex/mkh

@@ -0,0 +1,76 @@
+#! /bin/sh
+# mkh - pull headers out of C source
+PATH=/bin:/usr/bin ; export PATH
+
+# egrep pattern to pick out marked lines
+egrep='^ =([ 	]|$)'
+
+# Sed program to process marked lines into lines for the header file.
+# The markers have already been removed.  Two things are done here:  removal
+# of backslashed newlines, and some fudging of comments.  The first is done
+# because -o needs to have prototypes on one line to strip them down.
+# Getting comments into the output is tricky; we turn C++-style // comments
+# into /* */ comments, after altering any existing */'s to avoid trouble.
+peel='	/\\$/N
+	/\\\n[ 	]*/s///g
+	/\/\//s;\*/;* /;g
+	/\/\//s;//\(.*\);/*\1 */;'
+
+for a
+do
+	case "$a" in
+	-o)	# old (pre-function-prototype) compiler
+		# add code to comment out argument lists
+		peel="$peel
+			"'/^\([^#\/][^\/]*[a-zA-Z0-9_)]\)(\(.*\))/s;;\1(/*\2*/);'
+		shift
+		;;
+	-b)	# funny Berkeley __P macro
+		peel="$peel
+			"'/^\([^#\/][^\/]*[a-zA-Z0-9_)]\)(\(.*\))/s;;\1 __P((\2));'
+		shift
+		;;
+	-s)	# compiler doesn't like `static foo();'
+		# add code to get rid of the `static'
+		peel="$peel
+			"'/^static[ 	][^\/]*[a-zA-Z0-9_)](.*)/s;static.;;'
+		shift
+		;;
+	-p)	# private declarations
+		egrep='^ ==([ 	]|$)'
+		shift
+		;;
+	-i)	# wrap in #ifndef, argument is name
+		ifndef="$2"
+		shift ; shift
+		;;
+	*)	break
+		;;
+	esac
+done
+
+if test " $ifndef" != " "
+then
+	echo "#ifndef $ifndef"
+	echo "#define	$ifndef	/* never again */"
+fi
+echo "/* ========= begin header generated by $0 ========= */"
+echo '#ifdef __cplusplus'
+echo 'extern "C" {'
+echo '#endif'
+for f
+do
+	echo
+	echo "/* === $f === */"
+	egrep "$egrep" $f | sed 's/^ ==*[ 	]//;s/^ ==*$//' | sed "$peel"
+	echo
+done
+echo '#ifdef __cplusplus'
+echo '}'
+echo '#endif'
+echo "/* ========= end header generated by $0 ========= */"
+if test " $ifndef" != " "
+then
+	echo "#endif"
+fi
+exit 0

lib/libc/regex/re_format.7

@@ -0,0 +1,229 @@
+.TH REGEX 7 "17 May 1993"
+.BY "Henry Spencer"
+.SH NAME
+regex \- POSIX 1003.2 regular expressions
+.SH DESCRIPTION
+Regular expressions (``RE''s),
+as defined in POSIX 1003.2, come in two forms:
+modern REs (roughly those of
+.IR egrep ;
+1003.2 calls these ``extended'' REs)
+and obsolete REs (roughly those of
+.IR ed ;
+1003.2 ``basic'' REs).
+Obsolete REs mostly exist for backward compatibility in some old programs;
+they will be discussed at the end.
+1003.2 leaves some aspects of RE syntax and semantics open;
+`\(dg' marks decisions on these aspects that
+may not be fully portable to other 1003.2 implementations.
+.PP
+A (modern) RE is one\(dg or more non-empty\(dg \fIbranches\fR,
+separated by `|'.
+It matches anything that matches one of the branches.
+.PP
+A branch is one\(dg or more \fIpieces\fR, concatenated.
+It matches a match for the first, followed by a match for the second, etc.
+.PP
+A piece is an \fIatom\fR possibly followed
+by a single\(dg `*', `+', `?', or \fIbound\fR.
+An atom followed by `*' matches a sequence of 0 or more matches of the atom.
+An atom followed by `+' matches a sequence of 1 or more matches of the atom.
+An atom followed by `?' matches a sequence of 0 or 1 matches of the atom.
+.PP
+A \fIbound\fR is `{' followed by an unsigned decimal integer,
+possibly followed by `,'
+possibly followed by another unsigned decimal integer,
+always followed by `}'.
+The integers must lie between 0 and RE_DUP_MAX (255\(dg) inclusive,
+and if there are two of them, the first may not exceed the second.
+An atom followed by a bound containing one integer \fIi\fR
+and no comma matches
+a sequence of exactly \fIi\fR matches of the atom.
+An atom followed by a bound
+containing one integer \fIi\fR and a comma matches
+a sequence of \fIi\fR or more matches of the atom.
+An atom followed by a bound
+containing two integers \fIi\fR and \fIj\fR matches
+a sequence of \fIi\fR through \fIj\fR (inclusive) matches of the atom.
+.PP
+An atom is a regular expression enclosed in `()' (matching a match for the
+regular expression),
+an empty set of `()' (matching the null string)\(dg,
+a \fIbracket expression\fR (see below), `.'
+(matching any single character), `^' (matching the null string at the
+beginning of a line), `$' (matching the null string at the
+end of a line), a `\e' followed by one of the characters
+`^.[$()|*+?{\e'
+(matching that character taken as an ordinary character),
+a `\e' followed by any other character\(dg
+(matching that character taken as an ordinary character,
+as if the `\e' had not been present\(dg),
+or a single character with no other significance (matching that character).
+A `{' followed by a character other than a digit is an ordinary
+character, not the beginning of a bound\(dg.
+It is illegal to end an RE with `\e'.
+.PP
+A \fIbracket expression\fR is a list of characters enclosed in `[]'.
+It normally matches any single character from the list (but see below).
+If the list begins with `^',
+it matches any single character
+(but see below) \fInot\fR from the rest of the list.
+If two characters in the list are separated by `\-', this is shorthand
+for the full \fIrange\fR of characters between those two (inclusive) in the
+collating sequence,
+e.g. `[0-9]' in ASCII matches any decimal digit.
+It is illegal\(dg for two ranges to share an
+endpoint, e.g. `a-c-e'.
+Ranges are very collating-sequence-dependent,
+and portable programs should avoid relying on them.
+.PP
+To include a literal `]' in the list, make it the first character
+(following a possible `^').
+To include a literal `\-', make it the first or last character,
+or the second endpoint of a range.
+To use a literal `\-' as the first endpoint of a range,
+enclose it in `[.' and `.]' to make it a collating element (see below).
+With the exception of these and some combinations using `[' (see next
+paragraphs), all other special characters, including `\e', lose their
+special significance within a bracket expression.
+.PP
+Within a bracket expression, a collating element (a character,
+a multi-character sequence that collates as if it were a single character,
+or a collating-sequence name for either)
+enclosed in `[.' and `.]' stands for the
+sequence of characters of that collating element.
+The sequence is a single element of the bracket expression's list.
+A bracket expression containing a multi-character collating element 
+can thus match more than one character,
+e.g. if the collating sequence includes a `ch' collating element,
+then the RE `[[.ch.]]*c' matches the first five characters
+of `chchcc'.
+.PP
+Within a bracket expression, a collating element enclosed in `[=' and
+`=]' is an equivalence class, standing for the sequences of characters
+of all collating elements equivalent to that one, including itself.
+(If there are no other equivalent collating elements,
+the treatment is as if the enclosing delimiters were `[.' and `.]'.)
+For example, if o and \o'o^' are the members of an equivalence class,
+then `[[=o=]]', `[[=\o'o^'=]]', and `[o\o'o^']' are all synonymous.
+An equivalence class may not\(dg be an endpoint
+of a range.
+.PP
+Within a bracket expression, the name of a \fIcharacter class\fR enclosed
+in `[:' and `:]' stands for the list of all characters belonging to that
+class.
+Standard character class names are:
+.PP
+.RS
+.nf
+.ta 3c 6c 9c
+alnum	digit	punct
+alpha	graph	space
+blank	lower	upper
+cntrl	print	xdigit
+.fi
+.RE
+.PP
+These stand for the character classes defined in
+.IR ctype (3).
+A locale may provide others.
+A character class may not be used as an endpoint of a range.
+.PP
+There are two special cases\(dg of bracket expressions:
+the bracket expressions `[[:<:]]' and `[[:>:]]' match the null string at
+the beginning and end of a word respectively.
+A word is defined as a sequence of
+.I alnum
+characters (as defined by
+.IR ctype (3))
+which is neither preceded nor followed by
+.I alnum
+characters.
+This is an extension,
+compatible with but not specified by POSIX 1003.2,
+and should be used with
+caution in software intended to be portable to other systems.
+.PP
+In the event that an RE could match more than one substring of a given
+string,
+the RE matches the one starting earliest in the string.
+If the RE could match more than one substring starting at that point,
+it matches the longest.
+Subexpressions also match the longest possible substrings, subject to
+the constraint that the whole match be as long as possible,
+with subexpressions starting earlier in the RE taking priority over
+ones starting later.
+Note that higher-level subexpressions thus take priority over
+their lower-level component subexpressions.
+.PP
+Match lengths are measured in characters, not collating elements.
+A null string is considered longer than no match at all.
+For example,
+`bb*' matches the three middle characters of `abbbc',
+`(wee|week)(knights|nights)' matches all ten characters of `weeknights',
+when `(.*).*' is matched against `abc' the parenthesized subexpression
+matches all three characters, and
+when `(a*)*' is matched against `bc' both the whole RE and the parenthesized
+subexpression match the null string.
+.PP
+If case-independent matching is specified,
+the effect is much as if all case distinctions had vanished from the
+alphabet.
+When an alphabetic that exists in multiple cases appears as an
+ordinary character outside a bracket expression, it is effectively
+transformed into a bracket expression containing both cases,
+e.g. `x' becomes `[xX]'.
+When it appears inside a bracket expression, all case counterparts
+of it are added to the bracket expression, so that (e.g.) `[x]'
+becomes `[xX]' and `[^x]' becomes `[^xX]'.
+.PP
+No particular limit is imposed on the length of REs\(dg.
+Programs intended to be portable should not employ REs longer
+than 256 bytes,
+as an implementation can refuse to accept such REs and remain
+POSIX-compliant.
+.PP
+Obsolete (``basic'') regular expressions differ in several respects.
+`|', `+', and `?' are ordinary characters and there is no equivalent
+for their functionality.
+The delimiters for bounds are `\e{' and `\e}',
+with `{' and `}' by themselves ordinary characters.
+The parentheses for nested subexpressions are `\e(' and `\e)',
+with `(' and `)' by themselves ordinary characters.
+`^' is an ordinary character except at the beginning of the
+RE or\(dg the beginning of a parenthesized subexpression,
+`$' is an ordinary character except at the end of the
+RE or\(dg the end of a parenthesized subexpression,
+and `*' is an ordinary character if it appears at the beginning of the
+RE or the beginning of a parenthesized subexpression
+(after a possible leading `^').
+Finally, there is one new type of atom, a \fIback reference\fR:
+`\e' followed by a non-zero decimal digit \fId\fR
+matches the same sequence of characters
+matched by the \fId\fRth parenthesized subexpression
+(numbering subexpressions by the positions of their opening parentheses,
+left to right),
+so that (e.g.) `\e([bc]\e)\e1' matches `bb' or `cc' but not `bc'.
+.SH SEE ALSO
+regex(3)
+.PP
+POSIX 1003.2, section 2.8 (Regular Expression Notation).
+.SH BUGS
+Having two kinds of REs is a botch.
+.PP
+The current 1003.2 spec says that `)' is an ordinary character in
+the absence of an unmatched `(';
+this was an unintentional result of a wording error,
+and change is likely.
+Avoid relying on it.
+.PP
+Back references are a dreadful botch,
+posing major problems for efficient implementations.
+They are also somewhat vaguely defined
+(does
+`a\e(\e(b\e)*\e2\e)*d' match `abbbd'?).
+Avoid using them.
+.PP
+1003.2's specification of case-independent matching is vague.
+The ``one case implies all cases'' definition given above
+is current consensus among implementors as to the right interpretation.

lib/libc/regex/regcomp.ih

@@ -0,0 +1,51 @@
+/* ========= begin header generated by ./mkh ========= */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* === regcomp.c === */
+static void p_ere __P((register struct parse *p, int stop));
+static void p_ere_exp __P((register struct parse *p));
+static void p_str __P((register struct parse *p));
+static void p_bre __P((register struct parse *p, register int end1, register int end2));
+static int p_simp_re __P((register struct parse *p, int starordinary));
+static int p_count __P((register struct parse *p));
+static void p_bracket __P((register struct parse *p));
+static void p_b_term __P((register struct parse *p, register cset *cs));
+static void p_b_cclass __P((register struct parse *p, register cset *cs));
+static void p_b_eclass __P((register struct parse *p, register cset *cs));
+static char p_b_symbol __P((register struct parse *p));
+static char p_b_coll_elem __P((register struct parse *p, int endc));
+static char othercase __P((int ch));
+static void bothcases __P((register struct parse *p, int ch));
+static void ordinary __P((register struct parse *p, register int ch));
+static void nonnewline __P((register struct parse *p));
+static void repeat __P((register struct parse *p, sopno start, int from, int to));
+static int seterr __P((register struct parse *p, int e));
+static cset *allocset __P((register struct parse *p));
+static void freeset __P((register struct parse *p, register cset *cs));
+static int freezeset __P((register struct parse *p, register cset *cs));
+static int firstch __P((register struct parse *p, register cset *cs));
+static int nch __P((register struct parse *p, register cset *cs));
+static void mcadd __P((register struct parse *p, register cset *cs, register char *cp));
+static void mcsub __P((register cset *cs, register char *cp));
+static int mcin __P((register cset *cs, register char *cp));
+static char *mcfind __P((register cset *cs, register char *cp));
+static void mcinvert __P((register cset *cs));
+static void mccase __P((register cset *cs));
+static int isinsets __P((register struct re_guts *g, int c));
+static int samesets __P((register struct re_guts *g, int c1, int c2));
+static void categorize __P((struct parse *p, register struct re_guts *g));
+static sopno dupl __P((register struct parse *p, sopno start, sopno finish));
+static void doemit __P((register struct parse *p, sop op, size_t opnd));
+static void doinsert __P((register struct parse *p, sop op, size_t opnd, sopno pos));
+static void dofwd __P((register struct parse *p, sopno pos, sop value));
+static void enlarge __P((register struct parse *p, sopno size));
+static void stripsnug __P((register struct parse *p, register struct re_guts *g));
+static void findmust __P((register struct parse *p, register struct re_guts *g));
+static sopno pluscount __P((register struct parse *p, register struct re_guts *g));
+
+#ifdef __cplusplus
+}
+#endif
+/* ========= end header generated by ./mkh ========= */

lib/libc/regex/regerror.c

@@ -0,0 +1,127 @@
+#include <sys/types.h>
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <regex.h>
+
+#include "utils.h"
+#include "regerror.ih"
+
+/*
+ = #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 (!)
+ */
+static struct rerr {
+	int code;
+	char *name;
+	char *explain;
+} rerrs[] = {
+	REG_NOMATCH,	"REG_NOMATCH",	"regexec() failed to match",
+	REG_BADPAT,	"REG_BADPAT",	"invalid regular expression",
+	REG_ECOLLATE,	"REG_ECOLLATE",	"invalid collating element",
+	REG_ECTYPE,	"REG_ECTYPE",	"invalid character class",
+	REG_EESCAPE,	"REG_EESCAPE",	"trailing backslash (\\)",
+	REG_ESUBREG,	"REG_ESUBREG",	"invalid backreference number",
+	REG_EBRACK,	"REG_EBRACK",	"brackets ([ ]) not balanced",
+	REG_EPAREN,	"REG_EPAREN",	"parentheses not balanced",
+	REG_EBRACE,	"REG_EBRACE",	"braces not balanced",
+	REG_BADBR,	"REG_BADBR",	"invalid repetition count(s)",
+	REG_ERANGE,	"REG_ERANGE",	"invalid character range",
+	REG_ESPACE,	"REG_ESPACE",	"out of memory",
+	REG_BADRPT,	"REG_BADRPT",	"repetition-operator operand invalid",
+	REG_EMPTY,	"REG_EMPTY",	"empty (sub)expression",
+	REG_ASSERT,	"REG_ASSERT",	"\"can't happen\" -- you found a bug",
+	REG_INVARG,	"REG_INVARG",	"invalid argument to regex routine",
+	0,		"",		"*** unknown regexp error code ***",
+};
+
+/*
+ - regerror - the interface to error numbers
+ = extern size_t regerror(int errcode, const regex_t *preg, char *errbuf, \
+ =							size_t errbuf_size);
+ */
+/* ARGSUSED */
+size_t
+regerror(errcode, preg, errbuf, errbuf_size)
+int errcode;
+const regex_t *preg;
+char *errbuf;
+size_t errbuf_size;
+{
+	register struct rerr *r;
+	register size_t len;
+	register int target = errcode &~ REG_ITOA;
+	register char *s;
+	char convbuf[50];
+
+	if (errcode == REG_ATOI)
+		s = regatoi(preg, convbuf);
+	else {
+		for (r = rerrs; r->code != 0; r++)
+			if (r->code == target)
+				break;
+	
+		if (errcode&REG_ITOA) {
+			if (r->code != 0)
+				(void) strcpy(convbuf, r->name);
+			else
+				sprintf(convbuf, "REG_0x%x", target);
+			assert(strlen(convbuf) < sizeof(convbuf));
+			s = convbuf;
+		} else
+			s = r->explain;
+	}
+
+	len = strlen(s) + 1;
+	if (errbuf_size > 0) {
+		if (errbuf_size > len)
+			(void) strcpy(errbuf, s);
+		else {
+			(void) strncpy(errbuf, s, errbuf_size-1);
+			errbuf[errbuf_size-1] = '\0';
+		}
+	}
+
+	return(len);
+}
+
+/*
+ - regatoi - internal routine to implement REG_ATOI
+ = static char *regatoi(const regex_t *preg, char *localbuf);
+ */
+static char *
+regatoi(preg, localbuf)
+const regex_t *preg;
+char *localbuf;
+{
+	register struct rerr *r;
+	register size_t siz;
+	register char *p;
+
+	for (r = rerrs; r->code != 0; r++)
+		if (strcmp(r->name, preg->re_endp) == 0)
+			break;
+	if (r->code == 0)
+		return("0");
+
+	sprintf(localbuf, "%d", r->code);
+	return(localbuf);
+}

lib/libc/regex/regerror.ih

@@ -0,0 +1,11 @@
+/* ========= begin header generated by ./mkh ========= */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* === regerror.c === */
+
+#ifdef __cplusplus
+}
+#endif
+/* ========= end header generated by ./mkh ========= */

lib/libc/regex/regex.3

@@ -0,0 +1,502 @@
+.TH REGEX 3 "17 May 1993"
+.BY "Henry Spencer"
+.de ZR
+.\" one other place knows this name:  the SEE ALSO section
+.IR regex (7) \\$1
+..
+.SH NAME
+regcomp, regexec, regerror, regfree \- regular-expression library
+.SH SYNOPSIS
+.ft B
+.\".na
+#include <sys/types.h>
+.br
+#include <regex.h>
+.HP 10
+int regcomp(regex_t\ *preg, const\ char\ *pattern, int\ cflags);
+.HP
+int\ regexec(const\ regex_t\ *preg, const\ char\ *string,
+size_t\ nmatch, regmatch_t\ pmatch[], int\ eflags);
+.HP
+size_t\ regerror(int\ errcode, const\ regex_t\ *preg,
+char\ *errbuf, size_t\ errbuf_size);
+.HP
+void\ regfree(regex_t\ *preg);
+.\".ad
+.ft
+.SH DESCRIPTION
+These routines implement POSIX 1003.2 regular expressions (``RE''s);
+see
+.ZR .
+.I Regcomp
+compiles an RE written as a string into an internal form,
+.I regexec
+matches that internal form against a string and reports results,
+.I regerror
+transforms error codes from either into human-readable messages,
+and
+.I regfree
+frees any dynamically-allocated storage used by the internal form
+of an RE.
+.PP
+The header
+.I <regex.h>
+declares two structure types,
+.I regex_t
+and
+.IR regmatch_t ,
+the former for compiled internal forms and the latter for match reporting.
+It also declares the four functions,
+a type
+.IR regoff_t ,
+and a number of constants with names starting with ``REG_''.
+.PP
+.I Regcomp
+compiles the regular expression contained in the
+.I pattern
+string,
+subject to the flags in
+.IR cflags ,
+and places the results in the
+.I regex_t
+structure pointed to by
+.IR preg .
+.I Cflags
+is the bitwise OR of zero or more of the following flags:
+.IP REG_EXTENDED \w'REG_EXTENDED'u+2n
+Compile modern (``extended'') REs,
+rather than the obsolete (``basic'') REs that
+are the default.
+.IP REG_BASIC
+This is a synonym for 0,
+provided as a counterpart to REG_EXTENDED to improve readability.
+.IP REG_NOSPEC
+Compile with recognition of all special characters turned off.
+All characters are thus considered ordinary,
+so the ``RE'' is a literal string.
+This is an extension,
+compatible with but not specified by POSIX 1003.2,
+and should be used with
+caution in software intended to be portable to other systems.
+REG_EXTENDED and REG_NOSPEC may not be used
+in the same call to
+.IR regcomp .
+.IP REG_ICASE
+Compile for matching that ignores upper/lower case distinctions.
+See
+.ZR .
+.IP REG_NOSUB
+Compile for matching that need only report success or failure,
+not what was matched.
+.IP REG_NEWLINE
+Compile for newline-sensitive matching.
+By default, newline is a completely ordinary character with no special
+meaning in either REs or strings.
+With this flag,
+`[^' bracket expressions and `.' never match newline,
+a `^' anchor matches the null string after any newline in the string
+in addition to its normal function,
+and the `$' anchor matches the null string before any newline in the
+string in addition to its normal function.
+.IP REG_PEND
+The regular expression ends,
+not at the first NUL,
+but just before the character pointed to by the
+.I re_endp
+member of the structure pointed to by
+.IR preg .
+The
+.I re_endp
+member is of type
+.IR const\ char\ * .
+This flag permits inclusion of NULs in the RE;
+they are considered ordinary characters.
+This is an extension,
+compatible with but not specified by POSIX 1003.2,
+and should be used with
+caution in software intended to be portable to other systems.
+.PP
+When successful,
+.I regcomp
+returns 0 and fills in the structure pointed to by
+.IR preg .
+One member of that structure
+(other than
+.IR re_endp )
+is publicized:
+.IR re_nsub ,
+of type
+.IR size_t ,
+contains the number of parenthesized subexpressions within the RE
+(except that the value of this member is undefined if the
+REG_NOSUB flag was used).
+If
+.I regcomp
+fails, it returns a non-zero error code;
+see DIAGNOSTICS.
+.PP
+.I Regexec
+matches the compiled RE pointed to by
+.I preg
+against the
+.IR string ,
+subject to the flags in
+.IR eflags ,
+and reports results using
+.IR nmatch ,
+.IR pmatch ,
+and the returned value.
+The RE must have been compiled by a previous invocation of
+.IR regcomp .
+The compiled form is not altered during execution of
+.IR regexec ,
+so a single compiled RE can be used simultaneously by multiple threads.
+.PP
+By default,
+the NUL-terminated string pointed to by
+.I string
+is considered to be the text of an entire line, minus any terminating
+newline.
+The
+.I eflags
+argument is the bitwise OR of zero or more of the following flags:
+.IP REG_NOTBOL \w'REG_STARTEND'u+2n
+The first character of
+the string
+is not the beginning of a line, so the `^' anchor should not match before it.
+This does not affect the behavior of newlines under REG_NEWLINE.
+.IP REG_NOTEOL
+The NUL terminating
+the string
+does not end a line, so the `$' anchor should not match before it.
+This does not affect the behavior of newlines under REG_NEWLINE.
+.IP REG_STARTEND
+The string is considered to start at
+\fIstring\fR\ + \fIpmatch\fR[0].\fIrm_so\fR
+and to have a terminating NUL located at
+\fIstring\fR\ + \fIpmatch\fR[0].\fIrm_eo\fR
+(there need not actually be a NUL at that location),
+regardless of the value of
+.IR nmatch .
+See below for the definition of
+.IR pmatch
+and
+.IR nmatch .
+This is an extension,
+compatible with but not specified by POSIX 1003.2,
+and should be used with
+caution in software intended to be portable to other systems.
+Note that a non-zero \fIrm_so\fR does not imply REG_NOTBOL;
+REG_STARTEND affects only the location of the string,
+not how it is matched.
+.PP
+See
+.ZR
+for a discussion of what is matched in situations where an RE or a
+portion thereof could match any of several substrings of
+.IR string .
+.PP
+Normally,
+.I regexec
+returns 0 for success and the non-zero code REG_NOMATCH for failure.
+Other non-zero error codes may be returned in exceptional situations;
+see DIAGNOSTICS.
+.PP
+If REG_NOSUB was specified in the compilation of the RE,
+or if
+.I nmatch
+is 0,
+.I regexec
+ignores the
+.I pmatch
+argument (but see below for the case where REG_STARTEND is specified).
+Otherwise,
+.I pmatch
+points to an array of
+.I nmatch
+structures of type
+.IR regmatch_t .
+Such a structure has at least the members
+.I rm_so
+and
+.IR rm_eo ,
+both of type
+.I regoff_t
+(a signed arithmetic type at least as large as an
+.I off_t
+and a
+.IR ssize_t ),
+containing respectively the offset of the first character of a substring
+and the offset of the first character after the end of the substring.
+Offsets are measured from the beginning of the
+.I string
+argument given to
+.IR regexec .
+An empty substring is denoted by equal offsets,
+both indicating the character following the empty substring.
+.PP
+The 0th member of the
+.I pmatch
+array is filled in to indicate what substring of
+.I string
+was matched by the entire RE.
+Remaining members report what substring was matched by parenthesized
+subexpressions within the RE;
+member
+.I i
+reports subexpression
+.IR i ,
+with subexpressions counted (starting at 1) by the order of their opening
+parentheses in the RE, left to right.
+Unused entries in the array\(emcorresponding either to subexpressions that
+did not participate in the match at all, or to subexpressions that do not
+exist in the RE (that is, \fIi\fR\ > \fIpreg\fR\->\fIre_nsub\fR)\(emhave both
+.I rm_so
+and
+.I rm_eo
+set to \-1.
+If a subexpression participated in the match several times,
+the reported substring is the last one it matched.
+(Note, as an example in particular, that when the RE `(b*)+' matches `bbb',
+the parenthesized subexpression matches each of the three `b's and then
+an infinite number of empty strings following the last `b',
+so the reported substring is one of the empties.)
+.PP
+If REG_STARTEND is specified,
+.I pmatch
+must point to at least one
+.I regmatch_t
+(even if
+.I nmatch
+is 0 or REG_NOSUB was specified),
+to hold the input offsets for REG_STARTEND.
+Use for output is still entirely controlled by
+.IR nmatch ;
+if
+.I nmatch
+is 0 or REG_NOSUB was specified,
+the value of
+.IR pmatch [0]
+will not be changed by a successful
+.IR regexec .
+.PP
+.I Regerror
+maps a non-zero
+.I errcode
+from either
+.I regcomp
+or
+.I regexec
+to a human-readable, printable message.
+If
+.I preg
+is non-NULL,
+the error code should have arisen from use of
+the
+.I regex_t
+pointed to by
+.IR preg ,
+and if the error code came from
+.IR regcomp ,
+it should have been the result from the most recent
+.I regcomp
+using that
+.IR regex_t .
+.RI ( Regerror
+may be able to supply a more detailed message using information
+from the
+.IR regex_t .)
+.I Regerror
+places the NUL-terminated message into the buffer pointed to by
+.IR errbuf ,
+limiting the length (including the NUL) to at most
+.I errbuf_size
+bytes.
+If the whole message won't fit,
+as much of it as will fit before the terminating NUL is supplied.
+In any case,
+the returned value is the size of buffer needed to hold the whole
+message (including terminating NUL).
+If
+.I errbuf_size
+is 0,
+.I errbuf
+is ignored but the return value is still correct.
+.PP
+If the
+.I errcode
+given to
+.I regerror
+is first ORed with REG_ITOA,
+the ``message'' that results is the printable name of the error code,
+e.g. ``REG_NOMATCH'',
+rather than an explanation thereof.
+If
+.I errcode
+is REG_ATOI,
+then
+.I preg
+shall be non-NULL and the
+.I re_endp
+member of the structure it points to
+must point to the printable name of an error code;
+in this case, the result in
+.I errbuf
+is the decimal digits of
+the numeric value of the error code
+(0 if the name is not recognized).
+REG_ITOA and REG_ATOI are intended primarily as debugging facilities;
+they are extensions,
+compatible with but not specified by POSIX 1003.2,
+and should be used with
+caution in software intended to be portable to other systems.
+Be warned also that they are considered experimental and changes are possible.
+.PP
+.I Regfree
+frees any dynamically-allocated storage associated with the compiled RE
+pointed to by
+.IR preg .
+The remaining
+.I regex_t
+is no longer a valid compiled RE
+and the effect of supplying it to
+.I regexec
+or
+.I regerror
+is undefined.
+.PP
+None of these functions references global variables except for tables
+of constants;
+all are safe for use from multiple threads if the arguments are safe.
+.SH IMPLEMENTATION CHOICES
+There are a number of decisions that 1003.2 leaves up to the implementor,
+either by explicitly saying ``undefined'' or by virtue of them being
+forbidden by the RE grammar.
+This implementation treats them as follows.
+.PP
+See
+.ZR
+for a discussion of the definition of case-independent matching.
+.PP
+There is no particular limit on the length of REs,
+except insofar as memory is limited.
+Memory usage is approximately linear in RE size, and largely insensitive
+to RE complexity, except for bounded repetitions.
+See BUGS for one short RE using them
+that will run almost any system out of memory.
+.PP
+A backslashed character other than one specifically given a magic meaning
+by 1003.2 (such magic meanings occur only in obsolete [``basic''] REs)
+is taken as an ordinary character.
+.PP
+Any unmatched [ is a REG_EBRACK error.
+.PP
+Equivalence classes cannot begin or end bracket-expression ranges.
+The endpoint of one range cannot begin another.
+.PP
+RE_DUP_MAX, the limit on repetition counts in bounded repetitions, is 255.
+.PP
+A repetition operator (?, *, +, or bounds) cannot follow another
+repetition operator.
+A repetition operator cannot begin an expression or subexpression
+or follow `^' or `|'.
+.PP
+`|' cannot appear first or last in a (sub)expression or after another `|',
+i.e. an operand of `|' cannot be an empty subexpression.
+An empty parenthesized subexpression, `()', is legal and matches an
+empty (sub)string.
+An empty string is not a legal RE.
+.PP
+A `{' followed by a digit is considered the beginning of bounds for a
+bounded repetition, which must then follow the syntax for bounds.
+A `{' \fInot\fR followed by a digit is considered an ordinary character.
+.PP
+`^' and `$' beginning and ending subexpressions in obsolete (``basic'')
+REs are anchors, not ordinary characters.
+.SH SEE ALSO
+grep(1), regex(7)
+.PP
+POSIX 1003.2, sections 2.8 (Regular Expression Notation)
+and
+B.5 (C Binding for Regular Expression Matching).
+.SH DIAGNOSTICS
+Non-zero error codes from
+.I regcomp
+and
+.I regexec
+include the following:
+.PP
+.nf
+.ta \w'REG_ECOLLATE'u+3n
+REG_NOMATCH	regexec() failed to match
+REG_BADPAT	invalid regular expression
+REG_ECOLLATE	invalid collating element
+REG_ECTYPE	invalid character class
+REG_EESCAPE	\e applied to unescapable character
+REG_ESUBREG	invalid backreference number
+REG_EBRACK	brackets [ ] not balanced
+REG_EPAREN	parentheses ( ) not balanced
+REG_EBRACE	braces { } not balanced
+REG_BADBR	invalid repetition count(s) in { }
+REG_ERANGE	invalid character range in [ ]
+REG_ESPACE	ran out of memory
+REG_BADRPT	?, *, or + operand invalid
+REG_EMPTY	empty (sub)expression
+REG_ASSERT	``can't happen''\(emyou found a bug
+REG_INVARG	invalid argument, e.g. negative-length string
+.fi
+.SH HISTORY
+Written by Henry Spencer at University of Toronto,
+henry@zoo.toronto.edu.
+.SH BUGS
+This is an alpha release with known defects.
+Please report problems.
+.PP
+There is one known functionality bug.
+The implementation of internationalization is incomplete:
+the locale is always assumed to be the default one of 1003.2,
+and only the collating elements etc. of that locale are available.
+.PP
+The back-reference code is subtle and doubts linger about its correctness
+in complex cases.
+.PP
+.I Regexec
+performance is poor.
+This will improve with later releases.
+.I Nmatch
+exceeding 0 is expensive;
+.I nmatch
+exceeding 1 is worse.
+.I Regexec
+is largely insensitive to RE complexity \fIexcept\fR that back
+references are massively expensive.
+RE length does matter; in particular, there is a strong speed bonus
+for keeping RE length under about 30 characters,
+with most special characters counting roughly double.
+.PP
+.I Regcomp
+implements bounded repetitions by macro expansion,
+which is costly in time and space if counts are large
+or bounded repetitions are nested.
+An RE like, say,
+`((((a{1,100}){1,100}){1,100}){1,100}){1,100}'
+will (eventually) run almost any existing machine out of swap space.
+.PP
+There are suspected problems with response to obscure error conditions.
+Notably,
+certain kinds of internal overflow,
+produced only by truly enormous REs or by multiply nested bounded repetitions,
+are probably not handled well.
+.PP
+Due to a mistake in 1003.2, things like `a)b' are legal REs because `)' is
+a special character only in the presence of a previous unmatched `('.
+This can't be fixed until the spec is fixed.
+.PP
+The standard's definition of back references is vague.
+For example, does
+`a\e(\e(b\e)*\e2\e)*d' match `abbbd'?
+Until the standard is clarified,
+behavior in such cases should not be relied on.
+.PP
+The implementation of word-boundary matching is a bit of a kludge,
+and bugs may lurk in combinations of word-boundary matching and anchoring.

lib/libc/regex/regex.h

@@ -0,0 +1,74 @@
+#ifndef _REGEX_H_
+#define	_REGEX_H_	/* never again */
+/* ========= begin header generated by ./mkh ========= */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* === regex2.h === */
+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.c === */
+extern int regcomp __P((regex_t *preg, const char *pattern, int cflags));
+#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.c === */
+#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 (!) */
+extern size_t regerror __P((int errcode, const regex_t *preg, char *errbuf, size_t errbuf_size));
+static char *regatoi __P((const regex_t *preg, char *localbuf));
+
+
+/* === regexec.c === */
+extern int regexec __P((const regex_t *preg, const char *string, size_t nmatch, regmatch_t pmatch[], int eflags));
+#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 */
+
+
+/* === regfree.c === */
+extern void regfree __P((regex_t *preg));
+
+#ifdef __cplusplus
+}
+#endif
+/* ========= end header generated by ./mkh ========= */
+#endif

lib/libc/regex/regex2.h

@@ -0,0 +1,133 @@
+/*
+ * 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 {
+	uchar *ptr;		/* -> uchar [csetsize] */
+	uchar mask;		/* bit within array */
+	uchar 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[(uchar)(c)] |= (cs)->mask, (cs)->hash += (c))
+#define	CHsub(cs, c)	((cs)->ptr[(uchar)(c)] &= ~(cs)->mask, (cs)->hash -= (c))
+#define	CHIN(cs, c)	((cs)->ptr[(uchar)(c)] & (cs)->mask)
+#define	MCadd(cs, cp)	mcadd(p, cs, cp)	/* regcomp() internal fns */
+#define	MCsub(cs, cp)	mcsub(cs, cp)
+#define	MCin(cs, cp)	mcin(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] */
+	uchar *setbits;		/* -> uchar[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 */

lib/libc/regex/regexec.c

@@ -0,0 +1,139 @@
+/*
+ * the outer shell of regexec()
+ *
+ * This file includes engine.c *twice*, after muchos fiddling with the
+ * macros that code uses.  This lets the same code operate on two different
+ * representations for state sets.
+ */
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+#include <ctype.h>
+#include <regex.h>
+
+#include "utils.h"
+#include "regex2.h"
+
+static int nope = 0;		/* for use in asserts; shuts lint up */
+
+/* macros for manipulating states, small version */
+#define	states	long
+#define	states1	states		/* for later use in regexec() decision */
+#define	CLEAR(v)	((v) = 0)
+#define	SET0(v, n)	((v) &= ~(1 << (n)))
+#define	SET1(v, n)	((v) |= 1 << (n))
+#define	ISSET(v, n)	((v) & (1 << (n)))
+#define	ASSIGN(d, s)	((d) = (s))
+#define	EQ(a, b)	((a) == (b))
+#define	STATEVARS	int dummy	/* dummy version */
+#define	STATESETUP(m, n)	/* nothing */
+#define	STATETEARDOWN(m)	/* nothing */
+#define	SETUP(v)	((v) = 0)
+#define	onestate	int
+#define	INIT(o, n)	((o) = (unsigned)1 << (n))
+#define	INC(o)	((o) <<= 1)
+#define	ISSTATEIN(v, o)	((v) & (o))
+/* some abbreviations; note that some of these know variable names! */
+/* do "if I'm here, I can also be there" etc without branches */
+#define	FWD(dst, src, n)	((dst) |= ((unsigned)(src)&(here)) << (n))
+#define	BACK(dst, src, n)	((dst) |= ((unsigned)(src)&(here)) >> (n))
+#define	ISSETBACK(v, n)	((v) & ((unsigned)here >> (n)))
+/* function names */
+#define SNAMES			/* engine.c looks after details */
+
+#include "engine.c"
+
+/* now undo things */
+#undef	states
+#undef	CLEAR
+#undef	SET0
+#undef	SET1
+#undef	ISSET
+#undef	ASSIGN
+#undef	EQ
+#undef	STATEVARS
+#undef	STATESETUP
+#undef	STATETEARDOWN
+#undef	SETUP
+#undef	onestate
+#undef	INIT
+#undef	INC
+#undef	ISSTATEIN
+#undef	FWD
+#undef	BACK
+#undef	ISSETBACK
+#undef	SNAMES
+
+/* macros for manipulating states, large version */
+#define	states	char *
+#define	CLEAR(v)	memset(v, 0, m->g->nstates)
+#define	SET0(v, n)	((v)[n] = 0)
+#define	SET1(v, n)	((v)[n] = 1)
+#define	ISSET(v, n)	((v)[n])
+#define	ASSIGN(d, s)	memcpy(d, s, m->g->nstates)
+#define	EQ(a, b)	(memcmp(a, b, m->g->nstates) == 0)
+#define	STATEVARS	int vn; char *space
+#define	STATESETUP(m, nv)	{ (m)->space = malloc((nv)*(m)->g->nstates); \
+				if ((m)->space == NULL) return(REG_ESPACE); \
+				(m)->vn = 0; }
+#define	STATETEARDOWN(m)	{ free((m)->space); }
+#define	SETUP(v)	((v) = &m->space[m->vn++ * m->g->nstates])
+#define	onestate	int
+#define	INIT(o, n)	((o) = (n))
+#define	INC(o)	((o)++)
+#define	ISSTATEIN(v, o)	((v)[o])
+/* some abbreviations; note that some of these know variable names! */
+/* do "if I'm here, I can also be there" etc without branches */
+#define	FWD(dst, src, n)	((dst)[here+(n)] |= (src)[here])
+#define	BACK(dst, src, n)	((dst)[here-(n)] |= (src)[here])
+#define	ISSETBACK(v, n)	((v)[here - (n)])
+/* function names */
+#define	LNAMES			/* flag */
+
+#include "engine.c"
+
+/*
+ - regexec - interface for matching
+ = extern int regexec(const regex_t *preg, const char *string, size_t nmatch, \
+ =					regmatch_t pmatch[], int eflags);
+ = #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
+ *
+ * We put this here so we can exploit knowledge of the state representation
+ * when choosing which matcher to call.  Also, by this point the matchers
+ * have been prototyped.
+ */
+int				/* 0 success, REG_NOMATCH failure */
+regexec(preg, string, nmatch, pmatch, eflags)
+const regex_t *preg;
+const char *string;
+size_t nmatch;
+regmatch_t pmatch[];
+int eflags;
+{
+	register struct re_guts *g = preg->re_g;
+#ifdef REDEBUG
+#	define	GOODFLAGS(f)	(f)
+#else
+#	define	GOODFLAGS(f)	((f)&(REG_NOTBOL|REG_NOTEOL|REG_STARTEND))
+#endif
+
+	if (preg->re_magic != MAGIC1 || g->magic != MAGIC2)
+		return(REG_BADPAT);
+	assert(!(g->iflags&BAD));
+	if (g->iflags&BAD)		/* backstop for no-debug case */
+		return(REG_BADPAT);
+	if (eflags != GOODFLAGS(eflags))
+		return(REG_INVARG);
+
+	if (g->nstates <= CHAR_BIT*sizeof(states1) && !(eflags&REG_LARGE))
+		return(smatcher(g, (char *)string, nmatch, pmatch, eflags));
+	else
+		return(lmatcher(g, (char *)string, nmatch, pmatch, eflags));
+}

lib/libc/regex/regfree.c

@@ -0,0 +1,37 @@
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <regex.h>
+
+#include "utils.h"
+#include "regex2.h"
+
+/*
+ - regfree - free everything
+ = extern void regfree(regex_t *preg);
+ */
+void
+regfree(preg)
+regex_t *preg;
+{
+	register struct re_guts *g;
+
+	if (preg->re_magic != MAGIC1)	/* oops */
+		return;			/* nice to complain, but hard */
+
+	g = preg->re_g;
+	if (g == NULL || g->magic != MAGIC2)	/* oops again */
+		return;
+	preg->re_magic = 0;		/* mark it invalid */
+	g->magic = 0;			/* mark it invalid */
+
+	if (g->strip != NULL)
+		free((char *)g->strip);
+	if (g->sets != NULL)
+		free((char *)g->sets);
+	if (g->setbits != NULL)
+		free((char *)g->setbits);
+	if (g->must != NULL)
+		free(g->must);
+	free((char *)g);
+}

lib/libc/regex/split.c

@@ -0,0 +1,316 @@
+#include <stdio.h>
+#include <string.h>
+
+/*
+ - split - divide a string into fields, like awk split()
+ = int split(char *string, char *fields[], int nfields, char *sep);
+ */
+int				/* number of fields, including overflow */
+split(string, fields, nfields, sep)
+char *string;
+char *fields[];			/* list is not NULL-terminated */
+int nfields;			/* number of entries available in fields[] */
+char *sep;			/* "" white, "c" single char, "ab" [ab]+ */
+{
+	register char *p = string;
+	register char c;			/* latest character */
+	register char sepc = sep[0];
+	register char sepc2;
+	register int fn;
+	register char **fp = fields;
+	register char *sepp;
+	register int trimtrail;
+
+	/* white space */
+	if (sepc == '\0') {
+		while ((c = *p++) == ' ' || c == '\t')
+			continue;
+		p--;
+		trimtrail = 1;
+		sep = " \t";	/* note, code below knows this is 2 long */
+		sepc = ' ';
+	} else
+		trimtrail = 0;
+	sepc2 = sep[1];		/* now we can safely pick this up */
+
+	/* catch empties */
+	if (*p == '\0')
+		return(0);
+
+	/* single separator */
+	if (sepc2 == '\0') {
+		fn = nfields;
+		for (;;) {
+			*fp++ = p;
+			fn--;
+			if (fn == 0)
+				break;
+			while ((c = *p++) != sepc)
+				if (c == '\0')
+					return(nfields - fn);
+			*(p-1) = '\0';
+		}
+		/* we have overflowed the fields vector -- just count them */
+		fn = nfields;
+		for (;;) {
+			while ((c = *p++) != sepc)
+				if (c == '\0')
+					return(fn);
+			fn++;
+		}
+		/* not reached */
+	}
+
+	/* two separators */
+	if (sep[2] == '\0') {
+		fn = nfields;
+		for (;;) {
+			*fp++ = p;
+			fn--;
+			while ((c = *p++) != sepc && c != sepc2)
+				if (c == '\0') {
+					if (trimtrail && **(fp-1) == '\0')
+						fn++;
+					return(nfields - fn);
+				}
+			if (fn == 0)
+				break;
+			*(p-1) = '\0';
+			while ((c = *p++) == sepc || c == sepc2)
+				continue;
+			p--;
+		}
+		/* we have overflowed the fields vector -- just count them */
+		fn = nfields;
+		while (c != '\0') {
+			while ((c = *p++) == sepc || c == sepc2)
+				continue;
+			p--;
+			fn++;
+			while ((c = *p++) != '\0' && c != sepc && c != sepc2)
+				continue;
+		}
+		/* might have to trim trailing white space */
+		if (trimtrail) {
+			p--;
+			while ((c = *--p) == sepc || c == sepc2)
+				continue;
+			p++;
+			if (*p != '\0') {
+				if (fn == nfields+1)
+					*p = '\0';
+				fn--;
+			}
+		}
+		return(fn);
+	}
+
+	/* n separators */
+	fn = 0;
+	for (;;) {
+		if (fn < nfields)
+			*fp++ = p;
+		fn++;
+		for (;;) {
+			c = *p++;
+			if (c == '\0')
+				return(fn);
+			sepp = sep;
+			while ((sepc = *sepp++) != '\0' && sepc != c)
+				continue;
+			if (sepc != '\0')	/* it was a separator */
+				break;
+		}
+		if (fn < nfields)
+			*(p-1) = '\0';
+		for (;;) {
+			c = *p++;
+			sepp = sep;
+			while ((sepc = *sepp++) != '\0' && sepc != c)
+				continue;
+			if (sepc == '\0')	/* it wasn't a separator */
+				break;
+		}
+		p--;
+	}
+
+	/* not reached */
+}
+
+#ifdef TEST_SPLIT
+
+
+/*
+ * test program
+ * pgm		runs regression
+ * pgm sep	splits stdin lines by sep
+ * pgm str sep	splits str by sep
+ * pgm str sep n	splits str by sep n times
+ */
+int
+main(argc, argv)
+int argc;
+char *argv[];
+{
+	char buf[512];
+	register int n;
+#	define	MNF	10
+	char *fields[MNF];
+
+	if (argc > 4)
+		for (n = atoi(argv[3]); n > 0; n--) {
+			(void) strcpy(buf, argv[1]);
+		}
+	else if (argc > 3)
+		for (n = atoi(argv[3]); n > 0; n--) {
+			(void) strcpy(buf, argv[1]);
+			(void) split(buf, fields, MNF, argv[2]);
+		}
+	else if (argc > 2)
+		dosplit(argv[1], argv[2]);
+	else if (argc > 1)
+		while (fgets(buf, sizeof(buf), stdin) != NULL) {
+			buf[strlen(buf)-1] = '\0';	/* stomp newline */
+			dosplit(buf, argv[1]);
+		}
+	else
+		regress();
+
+	exit(0);
+}
+
+dosplit(string, seps)
+char *string;
+char *seps;
+{
+#	define	NF	5
+	char *fields[NF];
+	register int nf;
+
+	nf = split(string, fields, NF, seps);
+	print(nf, NF, fields);
+}
+
+print(nf, nfp, fields)
+int nf;
+int nfp;
+char *fields[];
+{
+	register int fn;
+	register int bound;
+
+	bound = (nf > nfp) ? nfp : nf;
+	printf("%d:\t", nf);
+	for (fn = 0; fn < bound; fn++)
+		printf("\"%s\"%s", fields[fn], (fn+1 < nf) ? ", " : "\n");
+}
+
+#define	RNF	5		/* some table entries know this */
+struct {
+	char *str;
+	char *seps;
+	int nf;
+	char *fi[RNF];
+} tests[] = {
+	"",		" ",	0,	{ "" },
+	" ",		" ",	2,	{ "", "" },
+	"x",		" ",	1,	{ "x" },
+	"xy",		" ",	1,	{ "xy" },
+	"x y",		" ",	2,	{ "x", "y" },
+	"abc def  g ",	" ",	5,	{ "abc", "def", "", "g", "" },
+	"  a bcd",	" ",	4,	{ "", "", "a", "bcd" },
+	"a b c d e f",	" ",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d ",	" ",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		" _",	0,	{ "" },
+	" ",		" _",	2,	{ "", "" },
+	"x",		" _",	1,	{ "x" },
+	"x y",		" _",	2,	{ "x", "y" },
+	"ab _ cd",	" _",	2,	{ "ab", "cd" },
+	" a_b  c ",	" _",	5,	{ "", "a", "b", "c", "" },
+	"a b c_d e f",	" _",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d ",	" _",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		" _~",	0,	{ "" },
+	" ",		" _~",	2,	{ "", "" },
+	"x",		" _~",	1,	{ "x" },
+	"x y",		" _~",	2,	{ "x", "y" },
+	"ab _~ cd",	" _~",	2,	{ "ab", "cd" },
+	" a_b  c~",	" _~",	5,	{ "", "a", "b", "c", "" },
+	"a b_c d~e f",	" _~",	6,	{ "a", "b", "c", "d", "e f" },
+	"~a b c d ",	" _~",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		" _~-",	0,	{ "" },
+	" ",		" _~-",	2,	{ "", "" },
+	"x",		" _~-",	1,	{ "x" },
+	"x y",		" _~-",	2,	{ "x", "y" },
+	"ab _~- cd",	" _~-",	2,	{ "ab", "cd" },
+	" a_b  c~",	" _~-",	5,	{ "", "a", "b", "c", "" },
+	"a b_c-d~e f",	" _~-",	6,	{ "a", "b", "c", "d", "e f" },
+	"~a-b c d ",	" _~-",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		"  ",	0,	{ "" },
+	" ",		"  ",	2,	{ "", "" },
+	"x",		"  ",	1,	{ "x" },
+	"xy",		"  ",	1,	{ "xy" },
+	"x y",		"  ",	2,	{ "x", "y" },
+	"abc def  g ",	"  ",	4,	{ "abc", "def", "g", "" },
+	"  a bcd",	"  ",	3,	{ "", "a", "bcd" },
+	"a b c d e f",	"  ",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d ",	"  ",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		"",	0,	{ "" },
+	" ",		"",	0,	{ "" },
+	"x",		"",	1,	{ "x" },
+	"xy",		"",	1,	{ "xy" },
+	"x y",		"",	2,	{ "x", "y" },
+	"abc def  g ",	"",	3,	{ "abc", "def", "g" },
+	"\t a bcd",	"",	2,	{ "a", "bcd" },
+	"  a \tb\t c ",	"",	3,	{ "a", "b", "c" },
+	"a b c d e ",	"",	5,	{ "a", "b", "c", "d", "e" },
+	"a b\tc d e f",	"",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d e f ",	"",	6,	{ "a", "b", "c", "d", "e f " },
+
+	NULL,		NULL,	0,	{ NULL },
+};
+
+regress()
+{
+	char buf[512];
+	register int n;
+	char *fields[RNF+1];
+	register int nf;
+	register int i;
+	register int printit;
+	register char *f;
+
+	for (n = 0; tests[n].str != NULL; n++) {
+		(void) strcpy(buf, tests[n].str);
+		fields[RNF] = NULL;
+		nf = split(buf, fields, RNF, tests[n].seps);
+		printit = 0;
+		if (nf != tests[n].nf) {
+			printf("split `%s' by `%s' gave %d fields, not %d\n",
+				tests[n].str, tests[n].seps, nf, tests[n].nf);
+			printit = 1;
+		} else if (fields[RNF] != NULL) {
+			printf("split() went beyond array end\n");
+			printit = 1;
+		} else {
+			for (i = 0; i < nf && i < RNF; i++) {
+				f = fields[i];
+				if (f == NULL)
+					f = "(NULL)";
+				if (strcmp(f, tests[n].fi[i]) != 0) {
+					printf("split `%s' by `%s', field %d is `%s', not `%s'\n",
+						tests[n].str, tests[n].seps,
+						i, fields[i], tests[n].fi[i]);
+					printit = 1;
+				}
+			}
+		}
+		if (printit)
+			print(nf, RNF, fields);
+	}
+}
+#endif

lib/libc/regex/stdlib.h

@@ -0,0 +1,2 @@
+extern char *malloc();
+extern char *realloc();

lib/libc/regex/tests

@@ -0,0 +1,436 @@
+# regular expression test set
+# Lines are at least three fields, separated by one or more tabs.  "" stands
+# for an empty field.  First field is an RE.  Second field is flags.  If
+# C flag given, regcomp() is expected to fail, and the third field is the
+# error name (minus the leading REG_).
+#
+# Otherwise it is expected to succeed, and the third field is the string to
+# try matching it against.  If there is no fourth field, the match is
+# expected to fail.  If there is a fourth field, it is the substring that
+# the RE is expected to match.  If there is a fifth field, it is a comma-
+# separated list of what the subexpressions should match, with - indicating
+# no match for that one.  In both the fourth and fifth fields, a (sub)field
+# starting with @ indicates that the (sub)expression is expected to match
+# a null string followed by the stuff after the @; this provides a way to
+# test where null strings match.  The character `N' in REs and strings
+# is newline, `S' is space, `T' is tab, `Z' is NUL.
+#
+# The full list of flags:
+#	-	placeholder, does nothing
+#	b	RE is a BRE, not an ERE
+#	&	try it as both an ERE and a BRE
+#	C	regcomp() error expected, third field is error name
+#	i	REG_ICASE
+#	m	("mundane") REG_NOSPEC
+#	s	REG_NOSUB (not really testable)
+#	n	REG_NEWLINE
+#	^	REG_NOTBOL
+#	$	REG_NOTEOL
+#	#	REG_STARTEND (see below)
+#	p	REG_PEND
+#
+# For REG_STARTEND, the start/end offsets are those of the substring
+# enclosed in ().
+
+# basics
+a		&	a	a
+abc		&	abc	abc
+abc|de		-	abc	abc
+a|b|c		-	abc	a
+
+# parentheses and perversions thereof
+a(b)c		-	abc	abc
+a\(b\)c		b	abc	abc
+a(		C	EPAREN
+a(		b	a(	a(
+a\(		-	a(	a(
+a\(		bC	EPAREN
+a\(b		bC	EPAREN
+a(b		C	EPAREN
+a(b		b	a(b	a(b
+# gag me with a right parenthesis -- 1003.2 goofed here (my fault, partly)
+a)		-	a)	a)
+)		-	)	)
+# end gagging (in a just world, those *should* give EPAREN)
+a)		b	a)	a)
+a\)		bC	EPAREN
+\)		bC	EPAREN
+a()b		-	ab	ab
+a\(\)b		b	ab	ab
+
+# anchoring and REG_NEWLINE
+^abc$		&	abc	abc
+a^b		-	a^b
+a^b		b	a^b	a^b
+a$b		-	a$b
+a$b		b	a$b	a$b
+^		&	abc	@abc
+$		&	abc	@
+^$		&	""	@
+$^		-	""	@
+\($\)\(^\)	b	""	@
+# stop retching, those are legitimate (although disgusting)
+^^		-	""	@
+$$		-	""	@
+b$		&	abNc
+b$		&n	abNc	b
+^b$		&	aNbNc
+^b$		&n	aNbNc	b
+^$		&n	aNNb	@Nb
+^$		n	abc
+^$		n	abcN	@
+$^		n	aNNb	@Nb
+\($\)\(^\)	bn	aNNb	@Nb
+^^		n^	aNNb	@Nb
+$$		n	aNNb	@NN
+^a		^	a
+a$		$	a
+^a		^n	aNb
+^b		^n	aNb	b
+a$		$n	bNa
+b$		$n	bNa	b
+a*(^b$)c*	-	b	b
+a*\(^b$\)c*	b	b	b
+
+# certain syntax errors and non-errors
+|		C	EMPTY
+|		b	|	|
+*		C	BADRPT
+*		b	*	*
++		C	BADRPT
+?		C	BADRPT
+""		&C	EMPTY
+()		-	abc	@abc
+\(\)		b	abc	@abc
+a||b		C	EMPTY
+|ab		C	EMPTY
+ab|		C	EMPTY
+(|a)b		C	EMPTY
+(a|)b		C	EMPTY
+(*a)		C	BADRPT
+(+a)		C	BADRPT
+(?a)		C	BADRPT
+({1}a)		C	BADRPT
+\(\{1\}a\)	bC	BADRPT
+(a|*b)		C	BADRPT
+(a|+b)		C	BADRPT
+(a|?b)		C	BADRPT
+(a|{1}b)	C	BADRPT
+^*		C	BADRPT
+^*		b	*	*
+^+		C	BADRPT
+^?		C	BADRPT
+^{1}		C	BADRPT
+^\{1\}		bC	BADRPT
+
+# metacharacters, backslashes
+a.c		&	abc	abc
+a[bc]d		&	abd	abd
+a\*c		&	a*c	a*c
+a\\b		&	a\b	a\b
+a\\\*b		&	a\*b	a\*b
+a\bc		&	abc	abc
+a\		&C	EESCAPE
+a\\bc		&	a\bc	a\bc
+\{		bC	BADRPT
+# trailing $ is a peculiar special case for the BRE code
+a$		&	a	a
+a$		&	a$
+a\$		&	a
+a\$		&	a$	a$
+a\\$		&	a
+a\\$		&	a$
+a\\$		&	a\$
+a\\$		&	a\	a\
+
+# back references, ugh
+a\(b\)\2c	bC	ESUBREG
+a\(b\1\)c	bC	ESUBREG
+a\(b*\)c\1d	b	abbcbbd	abbcbbd	bb
+a\(b*\)c\1d	b	abbcbd
+a\(b*\)c\1d	b	abbcbbbd
+^\(.\)\1	b	abc
+a\([bc]\)\1d	b	abcdabbd	abbd	b
+a\(\([bc]\)\2\)*d	b	abbccd	abbccd
+a\(\([bc]\)\2\)*d	b	abbcbd
+# actually, this next one probably ought to fail, but the spec is unclear
+a\(\(b\)*\2\)*d		b	abbbd	abbbd
+# here is a case that no NFA implementation does right
+\(ab*\)[ab]*\1	b	ababaaa	ababaaa	a
+# check out normal matching in the presence of back refs
+\(a\)\1bcd	b	aabcd	aabcd
+\(a\)\1bc*d	b	aabcd	aabcd
+\(a\)\1bc*d	b	aabd	aabd
+\(a\)\1bc*d	b	aabcccd	aabcccd
+\(a\)\1bc*[ce]d	b	aabcccd	aabcccd
+^\(a\)\1b\(c\)*cd$	b	aabcccd	aabcccd
+
+# ordinary repetitions
+ab*c		&	abc	abc
+ab+c		-	abc	abc
+ab?c		-	abc	abc
+a\(*\)b		b	a*b	a*b
+a\(**\)b	b	ab	ab
+a\(***\)b	bC	BADRPT
+*a		b	*a	*a
+**a		b	a	a
+***a		bC	BADRPT
+
+# the dreaded bounded repetitions
+{		&	{	{
+{abc		&	{abc	{abc
+{1		C	BADRPT
+{1}		C	BADRPT
+a{b		&	a{b	a{b
+a{1}b		-	ab	ab
+a\{1\}b		b	ab	ab
+a{1,}b		-	ab	ab
+a\{1,\}b	b	ab	ab
+a{1,2}b		-	aab	aab
+a\{1,2\}b	b	aab	aab
+a{1		C	EBRACE
+a\{1		bC	EBRACE
+a{1a		C	EBRACE
+a\{1a		bC	EBRACE
+a{1a}		C	BADBR
+a\{1a\}		bC	BADBR
+a{,2}		-	a{,2}	a{,2}
+a\{,2\}		bC	BADBR
+a{,}		-	a{,}	a{,}
+a\{,\}		bC	BADBR
+a{1,x}		C	BADBR
+a\{1,x\}	bC	BADBR
+a{1,x		C	EBRACE
+a\{1,x		bC	EBRACE
+a{300}		C	BADBR
+a\{300\}	bC	BADBR
+a{1,0}		C	BADBR
+a\{1,0\}	bC	BADBR
+ab{0,0}c	-	abcac	ac
+ab\{0,0\}c	b	abcac	ac
+ab{0,1}c	-	abcac	abc
+ab\{0,1\}c	b	abcac	abc
+ab{0,3}c	-	abbcac	abbc
+ab\{0,3\}c	b	abbcac	abbc
+ab{1,1}c	-	acabc	abc
+ab\{1,1\}c	b	acabc	abc
+ab{1,3}c	-	acabc	abc
+ab\{1,3\}c	b	acabc	abc
+ab{2,2}c	-	abcabbc	abbc
+ab\{2,2\}c	b	abcabbc	abbc
+ab{2,4}c	-	abcabbc	abbc
+ab\{2,4\}c	b	abcabbc	abbc
+((a{1,10}){1,10}){1,10}	-	a	a	a,a
+
+# multiple repetitions
+a**		&C	BADRPT
+a++		C	BADRPT
+a??		C	BADRPT
+a*+		C	BADRPT
+a*?		C	BADRPT
+a+*		C	BADRPT
+a+?		C	BADRPT
+a?*		C	BADRPT
+a?+		C	BADRPT
+a{1}{1}		C	BADRPT
+a*{1}		C	BADRPT
+a+{1}		C	BADRPT
+a?{1}		C	BADRPT
+a{1}*		C	BADRPT
+a{1}+		C	BADRPT
+a{1}?		C	BADRPT
+a*{b}		-	a{b}	a{b}
+a\{1\}\{1\}	bC	BADRPT
+a*\{1\}		bC	BADRPT
+a\{1\}*		bC	BADRPT
+
+# brackets, and numerous perversions thereof
+a[b]c		&	abc	abc
+a[ab]c		&	abc	abc
+a[^ab]c		&	adc	adc
+a[]b]c		&	a]c	a]c
+a[[b]c		&	a[c	a[c
+a[-b]c		&	a-c	a-c
+a[^]b]c		&	adc	adc
+a[^-b]c		&	adc	adc
+a[b-]c		&	a-c	a-c
+a[b		&C	EBRACK
+a[]		&C	EBRACK
+a[1-3]c		&	a2c	a2c
+a[3-1]c		&C	ERANGE
+a[1-3-5]c	&C	ERANGE
+a[[.-.]--]c	&	a-c	a-c
+a[1-		&C	ERANGE
+a[[.		&C	EBRACK
+a[[.x		&C	EBRACK
+a[[.x.		&C	EBRACK
+a[[.x.]		&C	EBRACK
+a[[.x.]]	&	ax	ax
+a[[.x,.]]	&C	ECOLLATE
+a[[.one.]]b	&	a1b	a1b
+a[[.notdef.]]b	&C	ECOLLATE
+a[[.].]]b	&	a]b	a]b
+a[[:alpha:]]c	&	abc	abc
+a[[:notdef:]]c	&C	ECTYPE
+a[[:		&C	EBRACK
+a[[:alpha	&C	EBRACK
+a[[:alpha:]	&C	EBRACK
+a[[:alpha,:]	&C	ECTYPE
+a[[:]:]]b	&C	ECTYPE
+a[[:-:]]b	&C	ECTYPE
+a[[:alph:]]	&C	ECTYPE
+a[[:alphabet:]]	&C	ECTYPE
+[[:alnum:]]+	-	-%@a0X-	a0X
+[[:alpha:]]+	-	-%@aX0-	aX
+[[:blank:]]+	-	aSSTb	SST
+[[:cntrl:]]+	-	aNTb	NT
+[[:digit:]]+	-	a019b	019
+[[:graph:]]+	-	Sa%bS	a%b
+[[:lower:]]+	-	AabC	ab
+[[:print:]]+	-	NaSbN	aSb
+[[:punct:]]+	-	S%-&T	%-&
+[[:space:]]+	-	aSNTb	SNT
+[[:upper:]]+	-	aBCd	BC
+[[:xdigit:]]+	-	p0f3Cq	0f3C
+a[[=b=]]c	&	abc	abc
+a[[=		&C	EBRACK
+a[[=b		&C	EBRACK
+a[[=b=		&C	EBRACK
+a[[=b=]		&C	EBRACK
+a[[=b,=]]	&C	ECOLLATE
+a[[=one=]]b	&	a1b	a1b
+
+# complexities
+a(((b)))c	-	abc	abc
+a(b|(c))d	-	abd	abd
+a(b*|c)d	-	abbd	abbd
+# just gotta have one DFA-buster, of course
+a[ab]{20}	-	aaaaabaaaabaaaabaaaab	aaaaabaaaabaaaabaaaab
+# and an inline expansion in case somebody gets tricky
+a[ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab]	-	aaaaabaaaabaaaabaaaab	aaaaabaaaabaaaabaaaab
+# and in case somebody just slips in an NFA...
+a[ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab](wee|week)(knights|night)	-	aaaaabaaaabaaaabaaaabweeknights	aaaaabaaaabaaaabaaaabweeknights
+# fish for anomalies as the number of states passes 32
+12345678901234567890123456789	-	a12345678901234567890123456789b	12345678901234567890123456789
+123456789012345678901234567890	-	a123456789012345678901234567890b	123456789012345678901234567890
+1234567890123456789012345678901	-	a1234567890123456789012345678901b	1234567890123456789012345678901
+12345678901234567890123456789012	-	a12345678901234567890123456789012b	12345678901234567890123456789012
+123456789012345678901234567890123	-	a123456789012345678901234567890123b	123456789012345678901234567890123
+# and one really big one, beyond any plausible word width
+1234567890123456789012345678901234567890123456789012345678901234567890	-	a1234567890123456789012345678901234567890123456789012345678901234567890b	1234567890123456789012345678901234567890123456789012345678901234567890
+
+# subtleties of matching
+abc		&	xabcy	abc
+a\(b\)?c\1d	b	acd
+aBc		i	Abc	Abc
+a[Bc]*d		i	abBCcd	abBCcd
+0[[:upper:]]1	&i	0a1	0a1
+0[[:lower:]]1	&i	0A1	0A1
+a[^b]c		&i	abc
+a[^b]c		&i	aBc
+a[^b]c		&i	adc	adc
+[a]b[c]		-	abc	abc
+[a]b[a]		-	aba	aba
+[abc]b[abc]	-	abc	abc
+[abc]b[abd]	-	abd	abd
+a(b?c)+d	-	accd	accd
+(wee|week)(knights|night)	-	weeknights	weeknights
+(we|wee|week|frob)(knights|night|day)	-	weeknights	weeknights
+a[bc]d		-	xyzaaabcaababdacd	abd
+a[ab]c		-	aaabc	abc
+abc		s	abc	abc
+
+# subexpressions
+a(b)(c)d	-	abcd	abcd	b,c
+a(((b)))c	-	abc	abc	b,b,b
+a(b|(c))d	-	abd	abd	b,-
+a(b*|c|e)d	-	abbd	abbd	bb
+a(b*|c|e)d	-	acd	acd	c
+a(b*|c|e)d	-	ad	ad	@d
+a(b?)c		-	abc	abc	b
+a(b?)c		-	ac	ac	@c
+a(b+)c		-	abc	abc	b
+a(b+)c		-	abbbc	abbbc	bbb
+a(b*)c		-	ac	ac	@c
+(a|ab)(bc([de]+)f|cde)	-	abcdef	abcdef	a,bcdef,de
+# the regression tester only asks for 9 subexpressions
+a(b)(c)(d)(e)(f)(g)(h)(i)(j)k	-	abcdefghijk	abcdefghijk	b,c,d,e,f,g,h,i,j
+a(b)(c)(d)(e)(f)(g)(h)(i)(j)(k)l	-	abcdefghijkl	abcdefghijkl	b,c,d,e,f,g,h,i,j,k
+a([bc]?)c	-	abc	abc	b
+a([bc]?)c	-	ac	ac	@c
+a([bc]+)c	-	abc	abc	b
+a([bc]+)c	-	abcc	abcc	bc
+a([bc]+)bc	-	abcbc	abcbc	bc
+a(bb+|b)b	-	abb	abb	b
+a(bbb+|bb+|b)b	-	abb	abb	b
+a(bbb+|bb+|b)b	-	abbb	abbb	bb
+a(bbb+|bb+|b)bb	-	abbb	abbb	b
+(.*).*		-	abcdef	abcdef	abcdef
+(a*)*		-	bc	@b	@b
+
+# do we get the right subexpression when it is used more than once?
+a(b|c)*d	-	ad	ad	-
+a(b|c)*d	-	abcd	abcd	c
+a(b|c)+d	-	abd	abd	b
+a(b|c)+d	-	abcd	abcd	c
+a(b|c?)+d	-	ad	ad	@d
+a(b|c?)+d	-	abcd	abcd	@d
+a(b|c){0,0}d	-	ad	ad	-
+a(b|c){0,1}d	-	ad	ad	-
+a(b|c){0,1}d	-	abd	abd	b
+a(b|c){0,2}d	-	ad	ad	-
+a(b|c){0,2}d	-	abcd	abcd	c
+a(b|c){0,}d	-	ad	ad	-
+a(b|c){0,}d	-	abcd	abcd	c
+a(b|c){1,1}d	-	abd	abd	b
+a(b|c){1,1}d	-	acd	acd	c
+a(b|c){1,2}d	-	abd	abd	b
+a(b|c){1,2}d	-	abcd	abcd	c
+a(b|c){1,}d	-	abd	abd	b
+a(b|c){1,}d	-	abcd	abcd	c
+a(b|c){2,2}d	-	acbd	acbd	b
+a(b|c){2,2}d	-	abcd	abcd	c
+a(b|c){2,4}d	-	abcd	abcd	c
+a(b|c){2,4}d	-	abcbd	abcbd	b
+a(b|c){2,4}d	-	abcbcd	abcbcd	c
+a(b|c){2,}d	-	abcd	abcd	c
+a(b|c){2,}d	-	abcbd	abcbd	b
+a(b+|((c)*))+d	-	abd	abd	@d,@d,-
+a(b+|((c)*))+d	-	abcd	abcd	@d,@d,-
+
+# check out the STARTEND option
+[abc]		&#	a(b)c	b
+[abc]		&#	a(d)c
+[abc]		&#	a(bc)d	b
+[abc]		&#	a(dc)d	c
+.		&#	a()c
+b.*c		&#	b(bc)c	bc
+b.*		&#	b(bc)c	bc
+.*c		&#	b(bc)c	bc
+
+# plain strings, with the NOSPEC flag
+abc		m	abc	abc
+abc		m	xabcy	abc
+abc		m	xyz
+a*b		m	aba*b	a*b
+a*b		m	ab
+""		mC	EMPTY
+
+# cases involving NULs
+aZb		&	a	a
+aZb		&p	a
+aZb		&p#	(aZb)	aZb
+aZ*b		&p#	(ab)	ab
+a.b		&#	(aZb)	aZb
+a.*		&#	(aZb)c	aZb
+
+# word boundaries (ick)
+[[:<:]]a	&	a	a
+[[:<:]]a	&	ba
+[[:<:]]a	&	-a	a
+a[[:>:]]	&	a	a
+a[[:>:]]	&	ab
+a[[:>:]]	&	a-	a
+[[:<:]]a.c[[:>:]]	&	axcd-dayc-dazce-abc	abc
+[[:<:]]a.c[[:>:]]	&	axcd-dayc-dazce-abc-q	abc
+[[:<:]]a.c[[:>:]]	&	axc-dayc-dazce-abc	axc

lib/libc/regex/utils.h

@@ -0,0 +1,13 @@
+/* utility definitions */
+#define	DUPMAX		_POSIX2_RE_DUP_MAX	/* xxx is this right? */
+#define	INFINITY	(DUPMAX + 1)
+#define	NC		(CHAR_MAX - CHAR_MIN + 1)
+
+typedef unsigned char uchar;
+
+#ifndef REDEBUG
+#ifndef NDEBUG
+#define	NDEBUG	/* no assertions please */
+#endif
+#endif
+#include <assert.h>

regress/lib/libc/regex/debug.c

@@ -0,0 +1,242 @@
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <regex.h>
+
+#include "utils.h"
+#include "regex2.h"
+#include "debug.ih"
+
+/*
+ - regprint - print a regexp for debugging
+ == void regprint(regex_t *r, FILE *d);
+ */
+void
+regprint(r, d)
+regex_t *r;
+FILE *d;
+{
+	register struct re_guts *g = r->re_g;
+	register int i;
+	register int c;
+	register int last;
+	int nincat[NC];
+
+	fprintf(d, "%ld states, %d categories", (long)g->nstates,
+							g->ncategories);
+	fprintf(d, ", first %ld last %ld", (long)g->firststate,
+						(long)g->laststate);
+	if (g->iflags&USEBOL)
+		fprintf(d, ", USEBOL");
+	if (g->iflags&USEEOL)
+		fprintf(d, ", USEEOL");
+	if (g->iflags&BAD)
+		fprintf(d, ", BAD");
+	if (g->nsub > 0)
+		fprintf(d, ", nsub=%ld", (long)g->nsub);
+	if (g->must != NULL)
+		fprintf(d, ", must(%ld) `%*s'", (long)g->mlen, (int)g->mlen,
+								g->must);
+	if (g->backrefs)
+		fprintf(d, ", backrefs");
+	if (g->nplus > 0)
+		fprintf(d, ", nplus %ld", (long)g->nplus);
+	fprintf(d, "\n");
+	s_print(g, d);
+	for (i = 0; i < g->ncategories; i++) {
+		nincat[i] = 0;
+		for (c = CHAR_MIN; c <= CHAR_MAX; c++)
+			if (g->categories[c] == i)
+				nincat[i]++;
+	}
+	fprintf(d, "cc0#%d", nincat[0]);
+	for (i = 1; i < g->ncategories; i++)
+		if (nincat[i] == 1) {
+			for (c = CHAR_MIN; c <= CHAR_MAX; c++)
+				if (g->categories[c] == i)
+					break;
+			fprintf(d, ", %d=%s", i, regchar(c));
+		}
+	fprintf(d, "\n");
+	for (i = 1; i < g->ncategories; i++)
+		if (nincat[i] != 1) {
+			fprintf(d, "cc%d\t", i);
+			last = -1;
+			for (c = CHAR_MIN; c <= CHAR_MAX+1; c++)	/* +1 does flush */
+				if (c <= CHAR_MAX && g->categories[c] == i) {
+					if (last < 0) {
+						fprintf(d, "%s", regchar(c));
+						last = c;
+					}
+				} else {
+					if (last >= 0) {
+						if (last != c-1)
+							fprintf(d, "-%s",
+								regchar(c-1));
+						last = -1;
+					}
+				}
+			fprintf(d, "\n");
+		}
+}
+
+/*
+ - s_print - print the strip for debugging
+ == static void s_print(register struct re_guts *g, FILE *d);
+ */
+static void
+s_print(g, d)
+register struct re_guts *g;
+FILE *d;
+{
+	register sop *s;
+	register cset *cs;
+	register int i;
+	register int done = 0;
+	register sop opnd;
+	register int col = 0;
+	register int last;
+	register sopno offset = 2;
+#	define	GAP()	{	if (offset % 5 == 0) { \
+					if (col > 40) { \
+						fprintf(d, "\n\t"); \
+						col = 0; \
+					} else { \
+						fprintf(d, " "); \
+						col++; \
+					} \
+				} else \
+					col++; \
+				offset++; \
+			}
+
+	if (OP(g->strip[0]) != OEND)
+		fprintf(d, "missing initial OEND!\n");
+	for (s = &g->strip[1]; !done; s++) {
+		opnd = OPND(*s);
+		switch (OP(*s)) {
+		case OEND:
+			fprintf(d, "\n");
+			done = 1;
+			break;
+		case OCHAR:
+			if (strchr("\\|()^$.[+*?{}!<> ", (char)opnd) != NULL)
+				fprintf(d, "\\%c", (char)opnd);
+			else
+				fprintf(d, "%s", regchar((char)opnd));
+			break;
+		case OBOL:
+			fprintf(d, "^");
+			break;
+		case OEOL:
+			fprintf(d, "$");
+			break;
+		case OBOW:
+			fprintf(d, "\\{");
+			break;
+		case OEOW:
+			fprintf(d, "\\}");
+			break;
+		case OANY:
+			fprintf(d, ".");
+			break;
+		case OANYOF:
+			fprintf(d, "[(%ld)", (long)opnd);
+			cs = &g->sets[opnd];
+			last = -1;
+			for (i = 0; i < g->csetsize+1; i++)	/* +1 flushes */
+				if (CHIN(cs, i) && i < g->csetsize) {
+					if (last < 0) {
+						fprintf(d, "%s", regchar(i));
+						last = i;
+					}
+				} else {
+					if (last >= 0) {
+						if (last != i-1)
+							fprintf(d, "-%s",
+								regchar(i-1));
+						last = -1;
+					}
+				}
+			fprintf(d, "]");
+			break;
+		case OBACK_:
+			fprintf(d, "(\\<%ld>", (long)opnd);
+			break;
+		case O_BACK:
+			fprintf(d, "<%ld>\\)", (long)opnd);
+			break;
+		case OPLUS_:
+			fprintf(d, "(+");
+			if (OP(*(s+opnd)) != O_PLUS)
+				fprintf(d, "<%ld>", (long)opnd);
+			break;
+		case O_PLUS:
+			if (OP(*(s-opnd)) != OPLUS_)
+				fprintf(d, "<%ld>", (long)opnd);
+			fprintf(d, "+)");
+			break;
+		case OQUEST_:
+			fprintf(d, "(?");
+			if (OP(*(s+opnd)) != O_QUEST)
+				fprintf(d, "<%ld>", (long)opnd);
+			break;
+		case O_QUEST:
+			if (OP(*(s-opnd)) != OQUEST_)
+				fprintf(d, "<%ld>", (long)opnd);
+			fprintf(d, "?)");
+			break;
+		case OLPAREN:
+			fprintf(d, "((<%ld>", (long)opnd);
+			break;
+		case ORPAREN:
+			fprintf(d, "<%ld>))", (long)opnd);
+			break;
+		case OCH_:
+			fprintf(d, "<");
+			if (OP(*(s+opnd)) != OOR2)
+				fprintf(d, "<%ld>", (long)opnd);
+			break;
+		case OOR1:
+			if (OP(*(s-opnd)) != OOR1 && OP(*(s-opnd)) != OCH_)
+				fprintf(d, "<%ld>", (long)opnd);
+			fprintf(d, "|");
+			break;
+		case OOR2:
+			fprintf(d, "|");
+			if (OP(*(s+opnd)) != OOR2 && OP(*(s+opnd)) != O_CH)
+				fprintf(d, "<%ld>", (long)opnd);
+			break;
+		case O_CH:
+			if (OP(*(s-opnd)) != OOR1)
+				fprintf(d, "<%ld>", (long)opnd);
+			fprintf(d, ">");
+			break;
+		default:
+			fprintf(d, "!%d(%d)!", OP(*s), opnd);
+			break;
+		}
+		if (!done)
+			GAP();
+	}
+}
+
+/*
+ - regchar - make a character printable
+ == static char *regchar(int ch);
+ */
+static char *			/* -> representation */
+regchar(ch)
+int ch;
+{
+	static char buf[10];
+
+	if (isprint(ch) || ch == ' ')
+		sprintf(buf, "%c", ch);
+	else
+		sprintf(buf, "\\%o", ch);
+	return(buf);
+}

regress/lib/libc/regex/debug.ih

@@ -0,0 +1,14 @@
+/* ========= begin header generated by ./mkh ========= */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* === debug.c === */
+void regprint __P((regex_t *r, FILE *d));
+static void s_print __P((register struct re_guts *g, FILE *d));
+static char *regchar __P((int ch));
+
+#ifdef __cplusplus
+}
+#endif
+/* ========= end header generated by ./mkh ========= */

regress/lib/libc/regex/main.c

@@ -0,0 +1,510 @@
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+#include <regex.h>
+#include <assert.h>
+
+#include "main.ih"
+
+char *progname;
+int debug = 0;
+int line = 0;
+int status = 0;
+
+int copts = REG_EXTENDED;
+int eopts = 0;
+regoff_t startoff = 0;
+regoff_t endoff = 0;
+
+
+extern int split();
+extern void regprint();
+
+/*
+ - main - do the simple case, hand off to regress() for regression
+ */
+main(argc, argv)
+int argc;
+char *argv[];
+{
+	regex_t re;
+#	define	NS	10
+	regmatch_t subs[NS];
+	char erbuf[100];
+	int err;
+	size_t len;
+	int c;
+	int errflg = 0;
+	register int i;
+	extern int optind;
+	extern char *optarg;
+
+	progname = argv[0];
+
+	while ((c = getopt(argc, argv, "c:e:S:E:x")) != EOF)
+		switch (c) {
+		case 'c':	/* compile options */
+			copts = options('c', optarg);
+			break;
+		case 'e':	/* execute options */
+			eopts = options('e', optarg);
+			break;
+		case 'S':	/* start offset */
+			startoff = (regoff_t)atoi(optarg);
+			break;
+		case 'E':	/* end offset */
+			endoff = (regoff_t)atoi(optarg);
+			break;
+		case 'x':	/* Debugging. */
+			debug++;
+			break;
+		case '?':
+		default:
+			errflg++;
+			break;
+		}
+	if (errflg) {
+		fprintf(stderr, "usage: %s ", progname);
+		fprintf(stderr, "[-c copt][-C][-d] [re]\n");
+		exit(2);
+	}
+
+	if (optind >= argc) {
+		regress(stdin);
+		exit(status);
+	}
+
+	err = regcomp(&re, argv[optind++], copts);
+	if (err) {
+		len = regerror(err, &re, erbuf, sizeof(erbuf));
+		fprintf(stderr, "error %s, %d/%d `%s'\n",
+			eprint(err), len, sizeof(erbuf), erbuf);
+		exit(status);
+	}
+	regprint(&re, stdout);	
+
+	if (optind >= argc) {
+		regfree(&re);
+		exit(status);
+	}
+
+	if (eopts&REG_STARTEND) {
+		subs[0].rm_so = startoff;
+		subs[0].rm_eo = strlen(argv[optind]) - endoff;
+	}
+	err = regexec(&re, argv[optind], (size_t)NS, subs, eopts);
+	if (err) {
+		len = regerror(err, &re, erbuf, sizeof(erbuf));
+		fprintf(stderr, "error %s, %d/%d `%s'\n",
+			eprint(err), len, sizeof(erbuf), erbuf);
+		exit(status);
+	}
+	if (!(copts&REG_NOSUB)) {
+		len = (int)(subs[0].rm_eo - subs[0].rm_so);
+		if (subs[0].rm_so != -1) {
+			if (len != 0)
+				printf("match `%.*s'\n", len,
+					argv[optind] + subs[0].rm_so);
+			else
+				printf("match `'@%.1s\n",
+					argv[optind] + subs[0].rm_so);
+		}
+		for (i = 1; i < NS; i++)
+			if (subs[i].rm_so != -1)
+				printf("(%d) `%.*s'\n", i,
+					(int)(subs[i].rm_eo - subs[i].rm_so),
+					argv[optind] + subs[i].rm_so);
+	}
+	exit(status);
+}
+
+/*
+ - regress - main loop of regression test
+ == void regress(FILE *in);
+ */
+void
+regress(in)
+FILE *in;
+{
+	char inbuf[1000];
+#	define	MAXF	10
+	char *f[MAXF];
+	int nf;
+	int i;
+	char erbuf[100];
+	size_t ne;
+	char *badpat = "invalid regular expression";
+#	define	SHORT	10
+	char *bpname = "REG_BADPAT";
+	regex_t re;
+
+	while (fgets(inbuf, sizeof(inbuf), in) != NULL) {
+		line++;
+		if (inbuf[0] == '#' || inbuf[0] == '\n')
+			continue;			/* NOTE CONTINUE */
+		inbuf[strlen(inbuf)-1] = '\0';	/* get rid of stupid \n */
+		if (debug)
+			fprintf(stdout, "%d:\n", line);
+		nf = split(inbuf, f, MAXF, "\t\t");
+		if (nf < 3) {
+			fprintf(stderr, "bad input, line %d\n", line);
+			exit(1);
+		}
+		for (i = 0; i < nf; i++)
+			if (strcmp(f[i], "\"\"") == 0)
+				f[i] = "";
+		if (nf <= 3)
+			f[3] = NULL;
+		if (nf <= 4)
+			f[4] = NULL;
+		try(f[0], f[1], f[2], f[3], f[4], options('c', f[1]));
+		if (opt('&', f[1]))	/* try with either type of RE */
+			try(f[0], f[1], f[2], f[3], f[4],
+					options('c', f[1]) &~ REG_EXTENDED);
+	}
+
+	ne = regerror(REG_BADPAT, (regex_t *)NULL, erbuf, sizeof(erbuf));
+	if (strcmp(erbuf, badpat) != 0 || ne != strlen(badpat)+1) {
+		fprintf(stderr, "end: regerror() test gave `%s' not `%s'\n",
+							erbuf, badpat);
+		status = 1;
+	}
+	ne = regerror(REG_BADPAT, (regex_t *)NULL, erbuf, (size_t)SHORT);
+	if (strncmp(erbuf, badpat, SHORT-1) != 0 || erbuf[SHORT-1] != '\0' ||
+						ne != strlen(badpat)+1) {
+		fprintf(stderr, "end: regerror() short test gave `%s' not `%.*s'\n",
+						erbuf, SHORT-1, badpat);
+		status = 1;
+	}
+	ne = regerror(REG_ITOA|REG_BADPAT, (regex_t *)NULL, erbuf, sizeof(erbuf));
+	if (strcmp(erbuf, bpname) != 0 || ne != strlen(bpname)+1) {
+		fprintf(stderr, "end: regerror() ITOA test gave `%s' not `%s'\n",
+						erbuf, bpname);
+		status = 1;
+	}
+	re.re_endp = bpname;
+	ne = regerror(REG_ATOI, &re, erbuf, sizeof(erbuf));
+	if (atoi(erbuf) != (int)REG_BADPAT) {
+		fprintf(stderr, "end: regerror() ATOI test gave `%s' not `%ld'\n",
+						erbuf, (long)REG_BADPAT);
+		status = 1;
+	} else if (ne != strlen(erbuf)+1) {
+		fprintf(stderr, "end: regerror() ATOI test len(`%s') = %ld\n",
+						erbuf, (long)REG_BADPAT);
+		status = 1;
+	}
+}
+
+/*
+ - try - try it, and report on problems
+ == void try(char *f0, char *f1, char *f2, char *f3, char *f4, int opts);
+ */
+void
+try(f0, f1, f2, f3, f4, opts)
+char *f0;
+char *f1;
+char *f2;
+char *f3;
+char *f4;
+int opts;			/* may not match f1 */
+{
+	regex_t re;
+#	define	NSUBS	10
+	regmatch_t subs[NSUBS];
+#	define	NSHOULD	15
+	char *should[NSHOULD];
+	int nshould;
+	char erbuf[100];
+	int err;
+	int len;
+	char *type = (opts & REG_EXTENDED) ? "ERE" : "BRE";
+	register int i;
+	char *grump;
+	char f0copy[1000];
+	char f2copy[1000];
+
+	strcpy(f0copy, f0);
+	re.re_endp = (opts&REG_PEND) ? f0copy + strlen(f0copy) : NULL;
+	fixstr(f0copy);
+	err = regcomp(&re, f0copy, opts);
+	if (err != 0 && (!opt('C', f1) || err != efind(f2))) {
+		/* unexpected error or wrong error */
+		len = regerror(err, &re, erbuf, sizeof(erbuf));
+		fprintf(stderr, "%d: %s error %s, %d/%d `%s'\n",
+					line, type, eprint(err), len,
+					sizeof(erbuf), erbuf);
+		status = 1;
+	} else if (err == 0 && opt('C', f1)) {
+		/* unexpected success */
+		fprintf(stderr, "%d: %s should have given REG_%s\n",
+						line, type, f2);
+		status = 1;
+		err = 1;	/* so we won't try regexec */
+	}
+
+	if (err != 0) {
+		regfree(&re);
+		return;
+	}
+
+	strcpy(f2copy, f2);
+	fixstr(f2copy);
+
+	if (options('e', f1)&REG_STARTEND) {
+		if (strchr(f2, '(') == NULL || strchr(f2, ')') == NULL)
+			fprintf(stderr, "%d: bad STARTEND syntax\n", line);
+		subs[0].rm_so = strchr(f2, '(') - f2 + 1;
+		subs[0].rm_eo = strchr(f2, ')') - f2;
+	}
+	err = regexec(&re, f2copy, NSUBS, subs, options('e', f1));
+
+	if (err != 0 && (f3 != NULL || err != REG_NOMATCH)) {
+		/* unexpected error or wrong error */
+		len = regerror(err, &re, erbuf, sizeof(erbuf));
+		fprintf(stderr, "%d: %s exec error %s, %d/%d `%s'\n",
+					line, type, eprint(err), len,
+					sizeof(erbuf), erbuf);
+		status = 1;
+	} else if (err != 0) {
+		/* nothing more to check */
+	} else if (f3 == NULL) {
+		/* unexpected success */
+		fprintf(stderr, "%d: %s exec should have failed\n",
+						line, type);
+		status = 1;
+		err = 1;		/* just on principle */
+	} else if (opts&REG_NOSUB) {
+		/* nothing more to check */
+	} else if ((grump = check(f2, subs[0], f3)) != NULL) {
+		fprintf(stderr, "%d: %s %s\n", line, type, grump);
+		status = 1;
+		err = 1;
+	}
+
+	if (err != 0 || f4 == NULL) {
+		regfree(&re);
+		return;
+	}
+
+	for (i = 1; i < NSHOULD; i++)
+		should[i] = NULL;
+	nshould = split(f4, should+1, NSHOULD-1, ",");
+	if (nshould == 0) {
+		nshould = 1;
+		should[1] = "";
+	}
+	for (i = 1; i < NSUBS; i++) {
+		grump = check(f2, subs[i], should[i]);
+		if (grump != NULL) {
+			fprintf(stderr, "%d: %s $%d %s\n", line,
+							type, i, grump);
+			status = 1;
+			err = 1;
+		}
+	}
+
+	regfree(&re);
+}
+
+/*
+ - options - pick options out of a regression-test string
+ == int options(int type, char *s);
+ */
+int
+options(type, s)
+int type;			/* 'c' compile, 'e' exec */
+char *s;
+{
+	register char *p;
+	register int o = (type == 'c') ? copts : eopts;
+	register char *legal = (type == 'c') ? "bisnmp" : "^$#tl";
+
+	for (p = s; *p != '\0'; p++)
+		if (strchr(legal, *p) != NULL)
+			switch (*p) {
+			case 'b':
+				o &= ~REG_EXTENDED;
+				break;
+			case 'i':
+				o |= REG_ICASE;
+				break;
+			case 's':
+				o |= REG_NOSUB;
+				break;
+			case 'n':
+				o |= REG_NEWLINE;
+				break;
+			case 'm':
+				o &= ~REG_EXTENDED;
+				o |= REG_NOSPEC;
+				break;
+			case 'p':
+				o |= REG_PEND;
+				break;
+			case '^':
+				o |= REG_NOTBOL;
+				break;
+			case '$':
+				o |= REG_NOTEOL;
+				break;
+			case '#':
+				o |= REG_STARTEND;
+				break;
+			case 't':	/* trace */
+				o |= REG_TRACE;
+				break;
+			case 'l':	/* force long representation */
+				o |= REG_LARGE;
+				break;
+			case 'r':	/* force backref use */
+				o |= REG_BACKR;
+				break;
+			}
+	return(o);
+}
+
+/*
+ - opt - is a particular option in a regression string?
+ == int opt(int c, char *s);
+ */
+int				/* predicate */
+opt(c, s)
+int c;
+char *s;
+{
+	return(strchr(s, c) != NULL);
+}
+
+/*
+ - fixstr - transform magic characters in strings
+ == void fixstr(register char *p);
+ */
+void
+fixstr(p)
+register char *p;
+{
+	if (p == NULL)
+		return;
+
+	for (; *p != '\0'; p++)
+		if (*p == 'N')
+			*p = '\n';
+		else if (*p == 'T')
+			*p = '\t';
+		else if (*p == 'S')
+			*p = ' ';
+		else if (*p == 'Z')
+			*p = '\0';
+}
+
+/*
+ - check - check a substring match
+ == char *check(char *str, regmatch_t sub, char *should);
+ */
+char *				/* NULL or complaint */
+check(str, sub, should)
+char *str;
+regmatch_t sub;
+char *should;
+{
+	register int len;
+	register int shlen;
+	register char *p;
+	static char grump[500];
+	register char *at = NULL;
+
+	if (should != NULL && strcmp(should, "-") == 0)
+		should = NULL;
+	if (should != NULL && should[0] == '@') {
+		at = should + 1;
+		should = "";
+	}
+
+	/* check rm_so and rm_eo for consistency */
+	if (sub.rm_so > sub.rm_eo || (sub.rm_so == -1 && sub.rm_eo != -1) ||
+				(sub.rm_so != -1 && sub.rm_eo == -1) ||
+				(sub.rm_so != -1 && sub.rm_so < 0) ||
+				(sub.rm_eo != -1 && sub.rm_eo < 0) ) {
+		sprintf(grump, "start %ld end %ld", (long)sub.rm_so,
+							(long)sub.rm_eo);
+		return(grump);
+	}
+
+	/* check for no match */
+	if (sub.rm_so == -1 && should == NULL)
+		return(NULL);
+	if (sub.rm_so == -1)
+		return("did not match");
+
+	/* check for in range */
+	if (sub.rm_eo > strlen(str)) {
+		sprintf(grump, "start %ld end %ld, past end of string",
+					(long)sub.rm_so, (long)sub.rm_eo);
+		return(grump);
+	}
+
+	len = (int)(sub.rm_eo - sub.rm_so);
+	shlen = (int)strlen(should);
+	p = str + sub.rm_so;
+
+	/* check for not supposed to match */
+	if (should == NULL) {
+		sprintf(grump, "matched `%.*s'", len, p);
+		return(grump);
+	}
+
+	/* check for wrong match */
+	if (len != shlen || strncmp(p, should, (size_t)shlen) != 0) {
+		sprintf(grump, "matched `%.*s' instead", len, p);
+		return(grump);
+	}
+	if (shlen > 0)
+		return(NULL);
+
+	/* check null match in right place */
+	if (at == NULL)
+		return(NULL);
+	shlen = strlen(at);
+	if (shlen == 0)
+		shlen = 1;	/* force check for end-of-string */
+	if (strncmp(p, at, shlen) != 0) {
+		sprintf(grump, "matched null at `%.20s'", p);
+		return(grump);
+	}
+	return(NULL);
+}
+
+/*
+ - eprint - convert error number to name
+ == static char *eprint(int err);
+ */
+static char *
+eprint(err)
+int err;
+{
+	static char epbuf[100];
+	size_t len;
+
+	len = regerror(REG_ITOA|err, (regex_t *)NULL, epbuf, sizeof(epbuf));
+	assert(len <= sizeof(epbuf));
+	return(epbuf);
+}
+
+/*
+ - efind - convert error name to number
+ == static int efind(char *name);
+ */
+static int
+efind(name)
+char *name;
+{
+	static char efbuf[100];
+	size_t n;
+	regex_t re;
+
+	sprintf(efbuf, "REG_%s", name);
+	assert(strlen(efbuf) < sizeof(efbuf));
+	re.re_endp = efbuf;
+	(void) regerror(REG_ATOI, &re, efbuf, sizeof(efbuf));
+	return(atoi(efbuf));
+}

regress/lib/libc/regex/main.ih

@@ -0,0 +1,19 @@
+/* ========= begin header generated by ./mkh ========= */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* === main.c === */
+void regress __P((FILE *in));
+void try __P((char *f0, char *f1, char *f2, char *f3, char *f4, int opts));
+int options __P((int type, char *s));
+int opt __P((int c, char *s));
+void fixstr __P((register char *p));
+char *check __P((char *str, regmatch_t sub, char *should));
+static char *eprint __P((int err));
+static int efind __P((char *name));
+
+#ifdef __cplusplus
+}
+#endif
+/* ========= end header generated by ./mkh ========= */

regress/lib/libc/regex/split.c

@@ -0,0 +1,316 @@
+#include <stdio.h>
+#include <string.h>
+
+/*
+ - split - divide a string into fields, like awk split()
+ = int split(char *string, char *fields[], int nfields, char *sep);
+ */
+int				/* number of fields, including overflow */
+split(string, fields, nfields, sep)
+char *string;
+char *fields[];			/* list is not NULL-terminated */
+int nfields;			/* number of entries available in fields[] */
+char *sep;			/* "" white, "c" single char, "ab" [ab]+ */
+{
+	register char *p = string;
+	register char c;			/* latest character */
+	register char sepc = sep[0];
+	register char sepc2;
+	register int fn;
+	register char **fp = fields;
+	register char *sepp;
+	register int trimtrail;
+
+	/* white space */
+	if (sepc == '\0') {
+		while ((c = *p++) == ' ' || c == '\t')
+			continue;
+		p--;
+		trimtrail = 1;
+		sep = " \t";	/* note, code below knows this is 2 long */
+		sepc = ' ';
+	} else
+		trimtrail = 0;
+	sepc2 = sep[1];		/* now we can safely pick this up */
+
+	/* catch empties */
+	if (*p == '\0')
+		return(0);
+
+	/* single separator */
+	if (sepc2 == '\0') {
+		fn = nfields;
+		for (;;) {
+			*fp++ = p;
+			fn--;
+			if (fn == 0)
+				break;
+			while ((c = *p++) != sepc)
+				if (c == '\0')
+					return(nfields - fn);
+			*(p-1) = '\0';
+		}
+		/* we have overflowed the fields vector -- just count them */
+		fn = nfields;
+		for (;;) {
+			while ((c = *p++) != sepc)
+				if (c == '\0')
+					return(fn);
+			fn++;
+		}
+		/* not reached */
+	}
+
+	/* two separators */
+	if (sep[2] == '\0') {
+		fn = nfields;
+		for (;;) {
+			*fp++ = p;
+			fn--;
+			while ((c = *p++) != sepc && c != sepc2)
+				if (c == '\0') {
+					if (trimtrail && **(fp-1) == '\0')
+						fn++;
+					return(nfields - fn);
+				}
+			if (fn == 0)
+				break;
+			*(p-1) = '\0';
+			while ((c = *p++) == sepc || c == sepc2)
+				continue;
+			p--;
+		}
+		/* we have overflowed the fields vector -- just count them */
+		fn = nfields;
+		while (c != '\0') {
+			while ((c = *p++) == sepc || c == sepc2)
+				continue;
+			p--;
+			fn++;
+			while ((c = *p++) != '\0' && c != sepc && c != sepc2)
+				continue;
+		}
+		/* might have to trim trailing white space */
+		if (trimtrail) {
+			p--;
+			while ((c = *--p) == sepc || c == sepc2)
+				continue;
+			p++;
+			if (*p != '\0') {
+				if (fn == nfields+1)
+					*p = '\0';
+				fn--;
+			}
+		}
+		return(fn);
+	}
+
+	/* n separators */
+	fn = 0;
+	for (;;) {
+		if (fn < nfields)
+			*fp++ = p;
+		fn++;
+		for (;;) {
+			c = *p++;
+			if (c == '\0')
+				return(fn);
+			sepp = sep;
+			while ((sepc = *sepp++) != '\0' && sepc != c)
+				continue;
+			if (sepc != '\0')	/* it was a separator */
+				break;
+		}
+		if (fn < nfields)
+			*(p-1) = '\0';
+		for (;;) {
+			c = *p++;
+			sepp = sep;
+			while ((sepc = *sepp++) != '\0' && sepc != c)
+				continue;
+			if (sepc == '\0')	/* it wasn't a separator */
+				break;
+		}
+		p--;
+	}
+
+	/* not reached */
+}
+
+#ifdef TEST_SPLIT
+
+
+/*
+ * test program
+ * pgm		runs regression
+ * pgm sep	splits stdin lines by sep
+ * pgm str sep	splits str by sep
+ * pgm str sep n	splits str by sep n times
+ */
+int
+main(argc, argv)
+int argc;
+char *argv[];
+{
+	char buf[512];
+	register int n;
+#	define	MNF	10
+	char *fields[MNF];
+
+	if (argc > 4)
+		for (n = atoi(argv[3]); n > 0; n--) {
+			(void) strcpy(buf, argv[1]);
+		}
+	else if (argc > 3)
+		for (n = atoi(argv[3]); n > 0; n--) {
+			(void) strcpy(buf, argv[1]);
+			(void) split(buf, fields, MNF, argv[2]);
+		}
+	else if (argc > 2)
+		dosplit(argv[1], argv[2]);
+	else if (argc > 1)
+		while (fgets(buf, sizeof(buf), stdin) != NULL) {
+			buf[strlen(buf)-1] = '\0';	/* stomp newline */
+			dosplit(buf, argv[1]);
+		}
+	else
+		regress();
+
+	exit(0);
+}
+
+dosplit(string, seps)
+char *string;
+char *seps;
+{
+#	define	NF	5
+	char *fields[NF];
+	register int nf;
+
+	nf = split(string, fields, NF, seps);
+	print(nf, NF, fields);
+}
+
+print(nf, nfp, fields)
+int nf;
+int nfp;
+char *fields[];
+{
+	register int fn;
+	register int bound;
+
+	bound = (nf > nfp) ? nfp : nf;
+	printf("%d:\t", nf);
+	for (fn = 0; fn < bound; fn++)
+		printf("\"%s\"%s", fields[fn], (fn+1 < nf) ? ", " : "\n");
+}
+
+#define	RNF	5		/* some table entries know this */
+struct {
+	char *str;
+	char *seps;
+	int nf;
+	char *fi[RNF];
+} tests[] = {
+	"",		" ",	0,	{ "" },
+	" ",		" ",	2,	{ "", "" },
+	"x",		" ",	1,	{ "x" },
+	"xy",		" ",	1,	{ "xy" },
+	"x y",		" ",	2,	{ "x", "y" },
+	"abc def  g ",	" ",	5,	{ "abc", "def", "", "g", "" },
+	"  a bcd",	" ",	4,	{ "", "", "a", "bcd" },
+	"a b c d e f",	" ",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d ",	" ",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		" _",	0,	{ "" },
+	" ",		" _",	2,	{ "", "" },
+	"x",		" _",	1,	{ "x" },
+	"x y",		" _",	2,	{ "x", "y" },
+	"ab _ cd",	" _",	2,	{ "ab", "cd" },
+	" a_b  c ",	" _",	5,	{ "", "a", "b", "c", "" },
+	"a b c_d e f",	" _",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d ",	" _",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		" _~",	0,	{ "" },
+	" ",		" _~",	2,	{ "", "" },
+	"x",		" _~",	1,	{ "x" },
+	"x y",		" _~",	2,	{ "x", "y" },
+	"ab _~ cd",	" _~",	2,	{ "ab", "cd" },
+	" a_b  c~",	" _~",	5,	{ "", "a", "b", "c", "" },
+	"a b_c d~e f",	" _~",	6,	{ "a", "b", "c", "d", "e f" },
+	"~a b c d ",	" _~",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		" _~-",	0,	{ "" },
+	" ",		" _~-",	2,	{ "", "" },
+	"x",		" _~-",	1,	{ "x" },
+	"x y",		" _~-",	2,	{ "x", "y" },
+	"ab _~- cd",	" _~-",	2,	{ "ab", "cd" },
+	" a_b  c~",	" _~-",	5,	{ "", "a", "b", "c", "" },
+	"a b_c-d~e f",	" _~-",	6,	{ "a", "b", "c", "d", "e f" },
+	"~a-b c d ",	" _~-",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		"  ",	0,	{ "" },
+	" ",		"  ",	2,	{ "", "" },
+	"x",		"  ",	1,	{ "x" },
+	"xy",		"  ",	1,	{ "xy" },
+	"x y",		"  ",	2,	{ "x", "y" },
+	"abc def  g ",	"  ",	4,	{ "abc", "def", "g", "" },
+	"  a bcd",	"  ",	3,	{ "", "a", "bcd" },
+	"a b c d e f",	"  ",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d ",	"  ",	6,	{ "", "a", "b", "c", "d " },
+
+	"",		"",	0,	{ "" },
+	" ",		"",	0,	{ "" },
+	"x",		"",	1,	{ "x" },
+	"xy",		"",	1,	{ "xy" },
+	"x y",		"",	2,	{ "x", "y" },
+	"abc def  g ",	"",	3,	{ "abc", "def", "g" },
+	"\t a bcd",	"",	2,	{ "a", "bcd" },
+	"  a \tb\t c ",	"",	3,	{ "a", "b", "c" },
+	"a b c d e ",	"",	5,	{ "a", "b", "c", "d", "e" },
+	"a b\tc d e f",	"",	6,	{ "a", "b", "c", "d", "e f" },
+	" a b c d e f ",	"",	6,	{ "a", "b", "c", "d", "e f " },
+
+	NULL,		NULL,	0,	{ NULL },
+};
+
+regress()
+{
+	char buf[512];
+	register int n;
+	char *fields[RNF+1];
+	register int nf;
+	register int i;
+	register int printit;
+	register char *f;
+
+	for (n = 0; tests[n].str != NULL; n++) {
+		(void) strcpy(buf, tests[n].str);
+		fields[RNF] = NULL;
+		nf = split(buf, fields, RNF, tests[n].seps);
+		printit = 0;
+		if (nf != tests[n].nf) {
+			printf("split `%s' by `%s' gave %d fields, not %d\n",
+				tests[n].str, tests[n].seps, nf, tests[n].nf);
+			printit = 1;
+		} else if (fields[RNF] != NULL) {
+			printf("split() went beyond array end\n");
+			printit = 1;
+		} else {
+			for (i = 0; i < nf && i < RNF; i++) {
+				f = fields[i];
+				if (f == NULL)
+					f = "(NULL)";
+				if (strcmp(f, tests[n].fi[i]) != 0) {
+					printf("split `%s' by `%s', field %d is `%s', not `%s'\n",
+						tests[n].str, tests[n].seps,
+						i, fields[i], tests[n].fi[i]);
+					printit = 1;
+				}
+			}
+		}
+		if (printit)
+			print(nf, RNF, fields);
+	}
+}
+#endif

regress/lib/libc/regex/tests

@@ -0,0 +1,436 @@
+# regular expression test set
+# Lines are at least three fields, separated by one or more tabs.  "" stands
+# for an empty field.  First field is an RE.  Second field is flags.  If
+# C flag given, regcomp() is expected to fail, and the third field is the
+# error name (minus the leading REG_).
+#
+# Otherwise it is expected to succeed, and the third field is the string to
+# try matching it against.  If there is no fourth field, the match is
+# expected to fail.  If there is a fourth field, it is the substring that
+# the RE is expected to match.  If there is a fifth field, it is a comma-
+# separated list of what the subexpressions should match, with - indicating
+# no match for that one.  In both the fourth and fifth fields, a (sub)field
+# starting with @ indicates that the (sub)expression is expected to match
+# a null string followed by the stuff after the @; this provides a way to
+# test where null strings match.  The character `N' in REs and strings
+# is newline, `S' is space, `T' is tab, `Z' is NUL.
+#
+# The full list of flags:
+#	-	placeholder, does nothing
+#	b	RE is a BRE, not an ERE
+#	&	try it as both an ERE and a BRE
+#	C	regcomp() error expected, third field is error name
+#	i	REG_ICASE
+#	m	("mundane") REG_NOSPEC
+#	s	REG_NOSUB (not really testable)
+#	n	REG_NEWLINE
+#	^	REG_NOTBOL
+#	$	REG_NOTEOL
+#	#	REG_STARTEND (see below)
+#	p	REG_PEND
+#
+# For REG_STARTEND, the start/end offsets are those of the substring
+# enclosed in ().
+
+# basics
+a		&	a	a
+abc		&	abc	abc
+abc|de		-	abc	abc
+a|b|c		-	abc	a
+
+# parentheses and perversions thereof
+a(b)c		-	abc	abc
+a\(b\)c		b	abc	abc
+a(		C	EPAREN
+a(		b	a(	a(
+a\(		-	a(	a(
+a\(		bC	EPAREN
+a\(b		bC	EPAREN
+a(b		C	EPAREN
+a(b		b	a(b	a(b
+# gag me with a right parenthesis -- 1003.2 goofed here (my fault, partly)
+a)		-	a)	a)
+)		-	)	)
+# end gagging (in a just world, those *should* give EPAREN)
+a)		b	a)	a)
+a\)		bC	EPAREN
+\)		bC	EPAREN
+a()b		-	ab	ab
+a\(\)b		b	ab	ab
+
+# anchoring and REG_NEWLINE
+^abc$		&	abc	abc
+a^b		-	a^b
+a^b		b	a^b	a^b
+a$b		-	a$b
+a$b		b	a$b	a$b
+^		&	abc	@abc
+$		&	abc	@
+^$		&	""	@
+$^		-	""	@
+\($\)\(^\)	b	""	@
+# stop retching, those are legitimate (although disgusting)
+^^		-	""	@
+$$		-	""	@
+b$		&	abNc
+b$		&n	abNc	b
+^b$		&	aNbNc
+^b$		&n	aNbNc	b
+^$		&n	aNNb	@Nb
+^$		n	abc
+^$		n	abcN	@
+$^		n	aNNb	@Nb
+\($\)\(^\)	bn	aNNb	@Nb
+^^		n^	aNNb	@Nb
+$$		n	aNNb	@NN
+^a		^	a
+a$		$	a
+^a		^n	aNb
+^b		^n	aNb	b
+a$		$n	bNa
+b$		$n	bNa	b
+a*(^b$)c*	-	b	b
+a*\(^b$\)c*	b	b	b
+
+# certain syntax errors and non-errors
+|		C	EMPTY
+|		b	|	|
+*		C	BADRPT
+*		b	*	*
++		C	BADRPT
+?		C	BADRPT
+""		&C	EMPTY
+()		-	abc	@abc
+\(\)		b	abc	@abc
+a||b		C	EMPTY
+|ab		C	EMPTY
+ab|		C	EMPTY
+(|a)b		C	EMPTY
+(a|)b		C	EMPTY
+(*a)		C	BADRPT
+(+a)		C	BADRPT
+(?a)		C	BADRPT
+({1}a)		C	BADRPT
+\(\{1\}a\)	bC	BADRPT
+(a|*b)		C	BADRPT
+(a|+b)		C	BADRPT
+(a|?b)		C	BADRPT
+(a|{1}b)	C	BADRPT
+^*		C	BADRPT
+^*		b	*	*
+^+		C	BADRPT
+^?		C	BADRPT
+^{1}		C	BADRPT
+^\{1\}		bC	BADRPT
+
+# metacharacters, backslashes
+a.c		&	abc	abc
+a[bc]d		&	abd	abd
+a\*c		&	a*c	a*c
+a\\b		&	a\b	a\b
+a\\\*b		&	a\*b	a\*b
+a\bc		&	abc	abc
+a\		&C	EESCAPE
+a\\bc		&	a\bc	a\bc
+\{		bC	BADRPT
+# trailing $ is a peculiar special case for the BRE code
+a$		&	a	a
+a$		&	a$
+a\$		&	a
+a\$		&	a$	a$
+a\\$		&	a
+a\\$		&	a$
+a\\$		&	a\$
+a\\$		&	a\	a\
+
+# back references, ugh
+a\(b\)\2c	bC	ESUBREG
+a\(b\1\)c	bC	ESUBREG
+a\(b*\)c\1d	b	abbcbbd	abbcbbd	bb
+a\(b*\)c\1d	b	abbcbd
+a\(b*\)c\1d	b	abbcbbbd
+^\(.\)\1	b	abc
+a\([bc]\)\1d	b	abcdabbd	abbd	b
+a\(\([bc]\)\2\)*d	b	abbccd	abbccd
+a\(\([bc]\)\2\)*d	b	abbcbd
+# actually, this next one probably ought to fail, but the spec is unclear
+a\(\(b\)*\2\)*d		b	abbbd	abbbd
+# here is a case that no NFA implementation does right
+\(ab*\)[ab]*\1	b	ababaaa	ababaaa	a
+# check out normal matching in the presence of back refs
+\(a\)\1bcd	b	aabcd	aabcd
+\(a\)\1bc*d	b	aabcd	aabcd
+\(a\)\1bc*d	b	aabd	aabd
+\(a\)\1bc*d	b	aabcccd	aabcccd
+\(a\)\1bc*[ce]d	b	aabcccd	aabcccd
+^\(a\)\1b\(c\)*cd$	b	aabcccd	aabcccd
+
+# ordinary repetitions
+ab*c		&	abc	abc
+ab+c		-	abc	abc
+ab?c		-	abc	abc
+a\(*\)b		b	a*b	a*b
+a\(**\)b	b	ab	ab
+a\(***\)b	bC	BADRPT
+*a		b	*a	*a
+**a		b	a	a
+***a		bC	BADRPT
+
+# the dreaded bounded repetitions
+{		&	{	{
+{abc		&	{abc	{abc
+{1		C	BADRPT
+{1}		C	BADRPT
+a{b		&	a{b	a{b
+a{1}b		-	ab	ab
+a\{1\}b		b	ab	ab
+a{1,}b		-	ab	ab
+a\{1,\}b	b	ab	ab
+a{1,2}b		-	aab	aab
+a\{1,2\}b	b	aab	aab
+a{1		C	EBRACE
+a\{1		bC	EBRACE
+a{1a		C	EBRACE
+a\{1a		bC	EBRACE
+a{1a}		C	BADBR
+a\{1a\}		bC	BADBR
+a{,2}		-	a{,2}	a{,2}
+a\{,2\}		bC	BADBR
+a{,}		-	a{,}	a{,}
+a\{,\}		bC	BADBR
+a{1,x}		C	BADBR
+a\{1,x\}	bC	BADBR
+a{1,x		C	EBRACE
+a\{1,x		bC	EBRACE
+a{300}		C	BADBR
+a\{300\}	bC	BADBR
+a{1,0}		C	BADBR
+a\{1,0\}	bC	BADBR
+ab{0,0}c	-	abcac	ac
+ab\{0,0\}c	b	abcac	ac
+ab{0,1}c	-	abcac	abc
+ab\{0,1\}c	b	abcac	abc
+ab{0,3}c	-	abbcac	abbc
+ab\{0,3\}c	b	abbcac	abbc
+ab{1,1}c	-	acabc	abc
+ab\{1,1\}c	b	acabc	abc
+ab{1,3}c	-	acabc	abc
+ab\{1,3\}c	b	acabc	abc
+ab{2,2}c	-	abcabbc	abbc
+ab\{2,2\}c	b	abcabbc	abbc
+ab{2,4}c	-	abcabbc	abbc
+ab\{2,4\}c	b	abcabbc	abbc
+((a{1,10}){1,10}){1,10}	-	a	a	a,a
+
+# multiple repetitions
+a**		&C	BADRPT
+a++		C	BADRPT
+a??		C	BADRPT
+a*+		C	BADRPT
+a*?		C	BADRPT
+a+*		C	BADRPT
+a+?		C	BADRPT
+a?*		C	BADRPT
+a?+		C	BADRPT
+a{1}{1}		C	BADRPT
+a*{1}		C	BADRPT
+a+{1}		C	BADRPT
+a?{1}		C	BADRPT
+a{1}*		C	BADRPT
+a{1}+		C	BADRPT
+a{1}?		C	BADRPT
+a*{b}		-	a{b}	a{b}
+a\{1\}\{1\}	bC	BADRPT
+a*\{1\}		bC	BADRPT
+a\{1\}*		bC	BADRPT
+
+# brackets, and numerous perversions thereof
+a[b]c		&	abc	abc
+a[ab]c		&	abc	abc
+a[^ab]c		&	adc	adc
+a[]b]c		&	a]c	a]c
+a[[b]c		&	a[c	a[c
+a[-b]c		&	a-c	a-c
+a[^]b]c		&	adc	adc
+a[^-b]c		&	adc	adc
+a[b-]c		&	a-c	a-c
+a[b		&C	EBRACK
+a[]		&C	EBRACK
+a[1-3]c		&	a2c	a2c
+a[3-1]c		&C	ERANGE
+a[1-3-5]c	&C	ERANGE
+a[[.-.]--]c	&	a-c	a-c
+a[1-		&C	ERANGE
+a[[.		&C	EBRACK
+a[[.x		&C	EBRACK
+a[[.x.		&C	EBRACK
+a[[.x.]		&C	EBRACK
+a[[.x.]]	&	ax	ax
+a[[.x,.]]	&C	ECOLLATE
+a[[.one.]]b	&	a1b	a1b
+a[[.notdef.]]b	&C	ECOLLATE
+a[[.].]]b	&	a]b	a]b
+a[[:alpha:]]c	&	abc	abc
+a[[:notdef:]]c	&C	ECTYPE
+a[[:		&C	EBRACK
+a[[:alpha	&C	EBRACK
+a[[:alpha:]	&C	EBRACK
+a[[:alpha,:]	&C	ECTYPE
+a[[:]:]]b	&C	ECTYPE
+a[[:-:]]b	&C	ECTYPE
+a[[:alph:]]	&C	ECTYPE
+a[[:alphabet:]]	&C	ECTYPE
+[[:alnum:]]+	-	-%@a0X-	a0X
+[[:alpha:]]+	-	-%@aX0-	aX
+[[:blank:]]+	-	aSSTb	SST
+[[:cntrl:]]+	-	aNTb	NT
+[[:digit:]]+	-	a019b	019
+[[:graph:]]+	-	Sa%bS	a%b
+[[:lower:]]+	-	AabC	ab
+[[:print:]]+	-	NaSbN	aSb
+[[:punct:]]+	-	S%-&T	%-&
+[[:space:]]+	-	aSNTb	SNT
+[[:upper:]]+	-	aBCd	BC
+[[:xdigit:]]+	-	p0f3Cq	0f3C
+a[[=b=]]c	&	abc	abc
+a[[=		&C	EBRACK
+a[[=b		&C	EBRACK
+a[[=b=		&C	EBRACK
+a[[=b=]		&C	EBRACK
+a[[=b,=]]	&C	ECOLLATE
+a[[=one=]]b	&	a1b	a1b
+
+# complexities
+a(((b)))c	-	abc	abc
+a(b|(c))d	-	abd	abd
+a(b*|c)d	-	abbd	abbd
+# just gotta have one DFA-buster, of course
+a[ab]{20}	-	aaaaabaaaabaaaabaaaab	aaaaabaaaabaaaabaaaab
+# and an inline expansion in case somebody gets tricky
+a[ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab]	-	aaaaabaaaabaaaabaaaab	aaaaabaaaabaaaabaaaab
+# and in case somebody just slips in an NFA...
+a[ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab][ab](wee|week)(knights|night)	-	aaaaabaaaabaaaabaaaabweeknights	aaaaabaaaabaaaabaaaabweeknights
+# fish for anomalies as the number of states passes 32
+12345678901234567890123456789	-	a12345678901234567890123456789b	12345678901234567890123456789
+123456789012345678901234567890	-	a123456789012345678901234567890b	123456789012345678901234567890
+1234567890123456789012345678901	-	a1234567890123456789012345678901b	1234567890123456789012345678901
+12345678901234567890123456789012	-	a12345678901234567890123456789012b	12345678901234567890123456789012
+123456789012345678901234567890123	-	a123456789012345678901234567890123b	123456789012345678901234567890123
+# and one really big one, beyond any plausible word width
+1234567890123456789012345678901234567890123456789012345678901234567890	-	a1234567890123456789012345678901234567890123456789012345678901234567890b	1234567890123456789012345678901234567890123456789012345678901234567890
+
+# subtleties of matching
+abc		&	xabcy	abc
+a\(b\)?c\1d	b	acd
+aBc		i	Abc	Abc
+a[Bc]*d		i	abBCcd	abBCcd
+0[[:upper:]]1	&i	0a1	0a1
+0[[:lower:]]1	&i	0A1	0A1
+a[^b]c		&i	abc
+a[^b]c		&i	aBc
+a[^b]c		&i	adc	adc
+[a]b[c]		-	abc	abc
+[a]b[a]		-	aba	aba
+[abc]b[abc]	-	abc	abc
+[abc]b[abd]	-	abd	abd
+a(b?c)+d	-	accd	accd
+(wee|week)(knights|night)	-	weeknights	weeknights
+(we|wee|week|frob)(knights|night|day)	-	weeknights	weeknights
+a[bc]d		-	xyzaaabcaababdacd	abd
+a[ab]c		-	aaabc	abc
+abc		s	abc	abc
+
+# subexpressions
+a(b)(c)d	-	abcd	abcd	b,c
+a(((b)))c	-	abc	abc	b,b,b
+a(b|(c))d	-	abd	abd	b,-
+a(b*|c|e)d	-	abbd	abbd	bb
+a(b*|c|e)d	-	acd	acd	c
+a(b*|c|e)d	-	ad	ad	@d
+a(b?)c		-	abc	abc	b
+a(b?)c		-	ac	ac	@c
+a(b+)c		-	abc	abc	b
+a(b+)c		-	abbbc	abbbc	bbb
+a(b*)c		-	ac	ac	@c
+(a|ab)(bc([de]+)f|cde)	-	abcdef	abcdef	a,bcdef,de
+# the regression tester only asks for 9 subexpressions
+a(b)(c)(d)(e)(f)(g)(h)(i)(j)k	-	abcdefghijk	abcdefghijk	b,c,d,e,f,g,h,i,j
+a(b)(c)(d)(e)(f)(g)(h)(i)(j)(k)l	-	abcdefghijkl	abcdefghijkl	b,c,d,e,f,g,h,i,j,k
+a([bc]?)c	-	abc	abc	b
+a([bc]?)c	-	ac	ac	@c
+a([bc]+)c	-	abc	abc	b
+a([bc]+)c	-	abcc	abcc	bc
+a([bc]+)bc	-	abcbc	abcbc	bc
+a(bb+|b)b	-	abb	abb	b
+a(bbb+|bb+|b)b	-	abb	abb	b
+a(bbb+|bb+|b)b	-	abbb	abbb	bb
+a(bbb+|bb+|b)bb	-	abbb	abbb	b
+(.*).*		-	abcdef	abcdef	abcdef
+(a*)*		-	bc	@b	@b
+
+# do we get the right subexpression when it is used more than once?
+a(b|c)*d	-	ad	ad	-
+a(b|c)*d	-	abcd	abcd	c
+a(b|c)+d	-	abd	abd	b
+a(b|c)+d	-	abcd	abcd	c
+a(b|c?)+d	-	ad	ad	@d
+a(b|c?)+d	-	abcd	abcd	@d
+a(b|c){0,0}d	-	ad	ad	-
+a(b|c){0,1}d	-	ad	ad	-
+a(b|c){0,1}d	-	abd	abd	b
+a(b|c){0,2}d	-	ad	ad	-
+a(b|c){0,2}d	-	abcd	abcd	c
+a(b|c){0,}d	-	ad	ad	-
+a(b|c){0,}d	-	abcd	abcd	c
+a(b|c){1,1}d	-	abd	abd	b
+a(b|c){1,1}d	-	acd	acd	c
+a(b|c){1,2}d	-	abd	abd	b
+a(b|c){1,2}d	-	abcd	abcd	c
+a(b|c){1,}d	-	abd	abd	b
+a(b|c){1,}d	-	abcd	abcd	c
+a(b|c){2,2}d	-	acbd	acbd	b
+a(b|c){2,2}d	-	abcd	abcd	c
+a(b|c){2,4}d	-	abcd	abcd	c
+a(b|c){2,4}d	-	abcbd	abcbd	b
+a(b|c){2,4}d	-	abcbcd	abcbcd	c
+a(b|c){2,}d	-	abcd	abcd	c
+a(b|c){2,}d	-	abcbd	abcbd	b
+a(b+|((c)*))+d	-	abd	abd	@d,@d,-
+a(b+|((c)*))+d	-	abcd	abcd	@d,@d,-
+
+# check out the STARTEND option
+[abc]		&#	a(b)c	b
+[abc]		&#	a(d)c
+[abc]		&#	a(bc)d	b
+[abc]		&#	a(dc)d	c
+.		&#	a()c
+b.*c		&#	b(bc)c	bc
+b.*		&#	b(bc)c	bc
+.*c		&#	b(bc)c	bc
+
+# plain strings, with the NOSPEC flag
+abc		m	abc	abc
+abc		m	xabcy	abc
+abc		m	xyz
+a*b		m	aba*b	a*b
+a*b		m	ab
+""		mC	EMPTY
+
+# cases involving NULs
+aZb		&	a	a
+aZb		&p	a
+aZb		&p#	(aZb)	aZb
+aZ*b		&p#	(ab)	ab
+a.b		&#	(aZb)	aZb
+a.*		&#	(aZb)c	aZb
+
+# word boundaries (ick)
+[[:<:]]a	&	a	a
+[[:<:]]a	&	ba
+[[:<:]]a	&	-a	a
+a[[:>:]]	&	a	a
+a[[:>:]]	&	ab
+a[[:>:]]	&	a-	a
+[[:<:]]a.c[[:>:]]	&	axcd-dayc-dazce-abc	abc
+[[:<:]]a.c[[:>:]]	&	axcd-dayc-dazce-abc-q	abc
+[[:<:]]a.c[[:>:]]	&	axc-dayc-dazce-abc	axc