services_mkdb; generate db file from services(5) to increase

speed of getserv*()

Obtained from:	NetBSD
MFC after:	2 weeks

5 files changed, 695 insertions, 0 deletions

diff --git a/usr.sbin/Makefile b/usr.sbin/Makefile
index 5df065f..c47ef76 100644
--- a/usr.sbin/Makefile
+++ b/usr.sbin/Makefile
@@ -167,6 +167,7 @@ SUBDIR=	${_ac} \
 	${_sade} \
 	${_sendmail} \
 	service \
+	services_mkdb \
 	setfib \
 	setfmac \
 	setpmac \
diff --git a/usr.sbin/services_mkdb/Makefile b/usr.sbin/services_mkdb/Makefile
new file mode 100644
index 0000000..659cdb8
--- /dev/null
+++ b/usr.sbin/services_mkdb/Makefile
@@ -0,0 +1,10 @@
+# $FreeBSD$
+
+PROG=	services_mkdb
+MAN=	services_mkdb.8
+SRCS=	services_mkdb.c uniq.c
+
+DPADD+=	${LIBUTIL}
+LDADD+=	-lutil
+
+.include <bsd.prog.mk>
diff --git a/usr.sbin/services_mkdb/services_mkdb.8 b/usr.sbin/services_mkdb/services_mkdb.8
new file mode 100644
index 0000000..6468fd2
--- /dev/null
+++ b/usr.sbin/services_mkdb/services_mkdb.8
@@ -0,0 +1,97 @@
+.\"	$NetBSD: services_mkdb.8,v 1.9 2009/05/13 22:36:39 wiz Exp $
+.\"
+.\" Copyright (c) 1999 The NetBSD Foundation, Inc.
+.\" All rights reserved.
+.\"
+.\" This code is derived from software contributed to The NetBSD Foundation
+.\" by Luke Mewburn.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+.\" POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd April 4, 2010
+.Dt SERVICES_MKDB 8
+.Os
+.Sh NAME
+.Nm services_mkdb
+.Nd generate the services databases
+.Sh SYNOPSIS
+.Nm
+.Op Fl q
+.Op Fl o Ar database
+.Op file
+.Nm
+.Fl u
+.Op file
+.Sh DESCRIPTION
+.Nm
+creates a
+.Xr db 3
+database for the specified file.
+If no file is specified, then
+.Pa /etc/services
+is used.
+The database is installed into
+.Pa /var/db/services.db .
+The file must be in the correct format (see
+.Xr services 5 ) .
+.Pp
+The options are as follows:
+.Bl -tag -width indent
+.It Fl o Ar database
+Put the output databases in the named file.
+.It Fl q
+Don't warn about duplicate services.
+.It Fl u
+Print the services file to stdout, omitting duplicate entries and comments.
+.El
+.Pp
+The databases are used by the C library services routines (see
+.Xr getservent 3 ) .
+.Pp
+.Nm
+exits zero on success, non-zero on failure.
+.Sh FILES
+.Bl -tag -width 24n -compact
+.It Pa /var/db/services.db
+The current services database.
+.It Pa /var/db/services.db.tmp
+A temporary file.
+.It Pa /etc/services
+The current services file.
+.El
+.Sh SEE ALSO
+.Xr db 3 ,
+.Xr getservent 3 ,
+.Xr services 5
+.Sh BUGS
+Because
+.Nm
+guarantees not to install a partial destination file it must
+build a temporary file in the same file system and if successful use
+.Xr rename 2
+to install over the destination file.
+.Pp
+If
+.Nm
+fails it will leave the previous version of the destination file intact.
diff --git a/usr.sbin/services_mkdb/services_mkdb.c b/usr.sbin/services_mkdb/services_mkdb.c
new file mode 100644
index 0000000..badea7c
--- /dev/null
+++ b/usr.sbin/services_mkdb/services_mkdb.c
@@ -0,0 +1,428 @@
+/*	$NetBSD: services_mkdb.c,v 1.14 2008/04/28 20:24:17 martin Exp $	*/
+
+/*-
+ * Copyright (c) 1999 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Luke Mewburn and Christos Zoulas.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/stat.h>
+
+#include <assert.h>
+#include <db.h>
+#include <err.h>
+#include <fcntl.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <libutil.h>
+#include <ctype.h>
+#include <errno.h>
+#include <stringlist.h>
+
+static char tname[MAXPATHLEN];
+
+#define	PMASK		0xffff
+#define PROTOMAX	5
+
+extern void	uniq(const char *);
+
+static void	add(DB *, StringList *, size_t, const char *, size_t *, int);
+static StringList ***parseservices(const char *, StringList *);
+static void	cleanup(void);
+static void	store(DB *, DBT *, DBT *, int);
+static void	killproto(DBT *);
+static char    *getstring(const char *, size_t, char **, const char *);
+static size_t	getprotoindex(StringList *, const char *);
+static const char *getprotostr(StringList *, size_t);
+static const char *mkaliases(StringList *, char *, size_t);
+static void	usage(void);
+
+const HASHINFO hinfo = {
+	.bsize = 256,
+	.ffactor = 4,
+	.nelem = 32768,
+	.cachesize = 1024,
+	.hash = NULL,
+	.lorder = 0
+};
+
+
+int
+main(int argc, char *argv[])
+{
+	DB	*db;
+	int	 ch;
+	const char *fname = _PATH_SERVICES;
+	const char *dbname = _PATH_SERVICES_DB;
+	int	 warndup = 1;
+	int	 unique = 0;
+	int	 otherflag = 0;
+	size_t	 cnt = 0;
+	StringList *sl, ***svc;
+	size_t port, proto;
+
+	setprogname(argv[0]);
+
+	while ((ch = getopt(argc, argv, "qo:u")) != -1)
+		switch (ch) {
+		case 'q':
+			otherflag = 1;
+			warndup = 0;
+			break;
+		case 'o':
+			otherflag = 1;
+			dbname = optarg;
+			break;
+		case 'u':
+			unique++;
+			break;
+		case '?':
+		default:
+			usage();
+		}
+
+	argc -= optind;
+	argv += optind;
+
+	if (argc > 1 || (unique && otherflag))
+		usage();
+	if (argc == 1)
+		fname = argv[0];
+
+	if (unique)
+		uniq(fname);
+
+	svc = parseservices(fname, sl = sl_init());
+
+	if (atexit(cleanup))
+		err(1, "Cannot install exit handler");
+
+	(void)snprintf(tname, sizeof(tname), "%s.tmp", dbname);
+	db = dbopen(tname, O_RDWR | O_CREAT | O_EXCL,
+	    (S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH), DB_HASH, &hinfo);
+	if (!db)
+		err(1, "Error opening temporary database `%s'", tname);
+
+
+	for (port = 0; port < PMASK + 1; port++) {
+		if (svc[port] == NULL)
+			continue;
+
+		for (proto = 0; proto < PROTOMAX; proto++) {
+			StringList *s;
+			if ((s = svc[port][proto]) == NULL)
+				continue;
+			add(db, s, port, getprotostr(sl, proto), &cnt, warndup);
+		}
+
+		free(svc[port]);
+	}
+
+	free(svc);
+	sl_free(sl, 1);
+
+	if ((db->close)(db))
+		err(1, "Error closing temporary database `%s'", tname);
+
+	if (rename(tname, dbname) == -1)
+		err(1, "Cannot rename `%s' to `%s'", tname, dbname);
+
+	return 0;
+}
+
+static void
+add(DB *db, StringList *sl, size_t port, const char *proto, size_t *cnt,
+    int warndup)
+{
+	size_t i;
+	char	 keyb[BUFSIZ], datab[BUFSIZ], abuf[BUFSIZ];
+	DBT	 data, key;
+	key.data = keyb;
+	data.data = datab;
+
+#ifdef DEBUG
+	(void)printf("add %s %zu %s [ ", sl->sl_str[0], port, proto);
+	for (i = 1; i < sl->sl_cur; i++)
+	    (void)printf("%s ", sl->sl_str[i]);
+	(void)printf("]\n");
+#endif
+
+	/* key `indirect key', data `full line' */
+	data.size = snprintf(datab, sizeof(datab), "%zu", (*cnt)++) + 1;
+	key.size = snprintf(keyb, sizeof(keyb), "%s %zu/%s %s",
+	    sl->sl_str[0], port, proto, mkaliases(sl, abuf, sizeof(abuf))) + 1;
+	store(db, &data, &key, warndup);
+
+	/* key `\377port/proto', data = `indirect key' */
+	key.size = snprintf(keyb, sizeof(keyb), "\377%zu/%s",
+	    port, proto) + 1;
+	store(db, &key, &data, warndup);
+
+	/* key `\377port', data = `indirect key' */
+	killproto(&key);
+	store(db, &key, &data, warndup);
+
+	/* add references for service and all aliases */
+	for (i = 0; i < sl->sl_cur; i++) {
+		/* key `\376service/proto', data = `indirect key' */
+		key.size = snprintf(keyb, sizeof(keyb), "\376%s/%s",
+		    sl->sl_str[i], proto) + 1;
+		store(db, &key, &data, warndup);
+
+		/* key `\376service', data = `indirect key' */
+		killproto(&key);
+		store(db, &key, &data, warndup);
+	}
+	sl_free(sl, 1);
+}
+
+static StringList ***
+parseservices(const char *fname, StringList *sl)
+{
+	size_t len, line, pindex;
+	FILE *fp;
+	StringList ***svc, *s;
+	char *p, *ep;
+
+	if ((fp = fopen(fname, "r")) == NULL)
+		err(1, "Cannot open `%s'", fname);
+
+	line = 0;
+	if ((svc = calloc(PMASK + 1, sizeof(StringList **))) == NULL)
+		err(1, "Cannot allocate %zu bytes", PMASK + 1);
+
+	/* XXX: change NULL to "\0\0#" when fparseln fixed */
+	for (; (p = fparseln(fp, &len, &line, NULL, 0)) != NULL; free(p)) {
+		char	*name, *port, *proto, *aliases, *cp, *alias;
+		unsigned long pnum;
+
+		if (len == 0)
+			continue;
+
+		for (cp = p; *cp && isspace((unsigned char)*cp); cp++)
+			continue;
+
+		if (*cp == '\0' || *cp == '#')
+			continue;
+
+		if ((name = getstring(fname, line, &cp, "name")) == NULL)
+			continue;
+
+		if ((port = getstring(fname, line, &cp, "port")) == NULL)
+			continue;
+
+		if (cp) {
+			for (aliases = cp; *cp && *cp != '#'; cp++)
+				continue;
+
+			if (*cp)
+				*cp = '\0';
+		} else
+			aliases = NULL;
+
+		proto = strchr(port, '/');
+		if (proto == NULL || proto[1] == '\0') {
+			warnx("%s, %zu: no protocol found", fname, line);
+			continue;
+		}
+		*proto++ = '\0';
+
+		errno = 0;
+		pnum = strtoul(port, &ep, 0);
+		if (*port == '\0' || *ep != '\0') {
+			warnx("%s, %zu: invalid port `%s'", fname, line, port);
+			continue;
+		}
+		if ((errno == ERANGE && pnum == ULONG_MAX) || pnum > PMASK) {
+			warnx("%s, %zu: port too big `%s'", fname, line, port);
+			continue;
+		}
+
+		if (svc[pnum] == NULL) {
+			svc[pnum] = calloc(PROTOMAX, sizeof(StringList *));
+			if (svc[pnum] == NULL)
+				err(1, "Cannot allocate %zu bytes", PROTOMAX);
+		}
+
+		pindex = getprotoindex(sl, proto);
+		if (svc[pnum][pindex] == NULL)
+			s = svc[pnum][pindex] = sl_init();
+		else
+			s = svc[pnum][pindex];
+
+		/* build list of aliases */
+		if (sl_find(s, name) == NULL) {
+			char *p;
+
+			if ((p = strdup(name)) == NULL)
+				err(1, "Cannot copy string");
+			(void)sl_add(s, p);
+		}
+
+		if (aliases) {
+			while ((alias = strsep(&aliases, " \t")) != NULL) {
+				if (alias[0] == '\0')
+					continue;
+				if (sl_find(s, alias) == NULL) {
+					char *p;
+
+					if ((p = strdup(alias)) == NULL)
+						err(1, "Cannot copy string");
+					(void)sl_add(s, p);
+				}
+			}
+		}
+	}
+	(void)fclose(fp);
+	return svc;
+}
+
+/*
+ * cleanup(): Remove temporary files upon exit
+ */
+static void
+cleanup(void)
+{
+	if (tname[0])
+		(void)unlink(tname);
+}
+
+static char *
+getstring(const char *fname, size_t line, char **cp, const char *tag)
+{
+	char *str;
+
+	while ((str = strsep(cp, " \t")) != NULL && *str == '\0')
+		continue;
+
+	if (str == NULL)
+		warnx("%s, %zu: no %s found", fname, line, tag);
+
+	return str;
+}
+
+static void
+killproto(DBT *key)
+{
+	char *p, *d = key->data;
+
+	if ((p = strchr(d, '/')) == NULL)
+		abort();
+	*p++ = '\0';
+	key->size = p - d;
+}
+
+static void
+store(DB *db, DBT *key, DBT *data, int warndup)
+{
+#ifdef DEBUG
+	int k = key->size - 1;
+	int d = data->size - 1;
+	(void)printf("store [%*.*s] [%*.*s]\n",
+		k, k, (char *)key->data + 1,
+		d, d, (char *)data->data + 1);
+#endif
+	switch ((db->put)(db, key, data, R_NOOVERWRITE)) {
+	case 0:
+		break;
+	case 1:
+		if (warndup)
+			warnx("duplicate service `%s'",
+			    &((char *)key->data)[1]);
+		break;
+	case -1:
+		err(1, "put");
+		break;
+	default:
+		abort();
+		break;
+	}
+}
+
+static size_t
+getprotoindex(StringList *sl, const char *str)
+{
+	size_t i;
+	char *p;
+
+	for (i= 0; i < sl->sl_cur; i++)
+		if (strcmp(sl->sl_str[i], str) == 0)
+			return i;
+
+	if (i == PROTOMAX)
+		errx(1, "Ran out of protocols adding `%s';"
+		    " recompile with larger PROTOMAX", str);
+	if ((p = strdup(str)) == NULL)
+		err(1, "Cannot copy string");
+	(void)sl_add(sl, p);
+	return i;
+}
+
+static const char *
+getprotostr(StringList *sl, size_t i)
+{
+	assert(i < sl->sl_cur);
+	return sl->sl_str[i];
+}
+
+static const char *
+mkaliases(StringList *sl, char *buf, size_t len)
+{
+	size_t nc, i, pos;
+
+	buf[0] = 0;
+	for (i = 1, pos = 0; i < sl->sl_cur; i++) {
+		nc = strlcpy(buf + pos, sl->sl_str[i], len);
+		if (nc >= len)
+			goto out;
+		pos += nc;
+		len -= nc;
+		nc = strlcpy(buf + pos, " ", len);
+		if (nc >= len)
+			goto out;
+		pos += nc;
+		len -= nc;
+	}
+	return buf;
+out:
+	warn("aliases for `%s' truncated", sl->sl_str[0]);
+	return buf;
+}
+
+static void
+usage(void)
+{
+	(void)fprintf(stderr, "Usage:\t%s [-q] [-o <db>] [<servicefile>]\n"
+	    "\t%s -u [<servicefile>]\n", getprogname(), getprogname());
+	exit(1);
+}
diff --git a/usr.sbin/services_mkdb/uniq.c b/usr.sbin/services_mkdb/uniq.c
new file mode 100644
index 0000000..0674b4b
--- /dev/null
+++ b/usr.sbin/services_mkdb/uniq.c
@@ -0,0 +1,159 @@
+/*	$NetBSD: uniq.c,v 1.4 2008/04/28 20:24:17 martin Exp $	*/
+
+/*-
+ * Copyright (c) 2007 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Christos Zoulas.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <db.h>
+#include <err.h>
+#include <libutil.h>
+#include <ctype.h>
+#include <fcntl.h>
+
+extern const HASHINFO hinfo;
+
+void uniq(const char *);
+static int comp(const char *, char **, size_t *);
+
+/*
+ * Preserve only unique content lines in a file. Input lines that have
+ * content [alphanumeric characters before a comment] are white-space
+ * normalized and have their comments removed. Then they are placed
+ * in a hash table, and only the first instance of them is printed.
+ * Comment lines without any alphanumeric content are always printed
+ * since they are there to make the file "pretty". Comment lines with
+ * alphanumeric content are also placed into the hash table and only
+ * printed once.
+ */
+void
+uniq(const char *fname)
+{
+	DB *db;
+	DBT key;
+	static const DBT data = { NULL, 0 };
+	FILE *fp;
+	char *line;
+	size_t len;
+
+	if ((db = dbopen(NULL, O_RDWR, 0, DB_HASH, &hinfo)) == NULL)
+		err(1, "Cannot create in memory database");
+
+	if ((fp = fopen(fname, "r")) == NULL)
+		err(1, "Cannot open `%s'", fname);
+	while ((line = fgetln(fp, &len)) != NULL) {
+		size_t complen = len;
+		char *compline;
+		if (!comp(line, &compline, &complen)) {
+			(void)fprintf(stdout, "%*.*s", (int)len, (int)len,
+			    line);
+			continue;
+		}
+		key.data = compline;
+		key.size = complen;
+		switch ((db->put)(db, &key, &data, R_NOOVERWRITE)) {
+		case 0:
+			(void)fprintf(stdout, "%*.*s", (int)len, (int)len,
+			    line);
+			break;
+		case 1:
+			break;
+		case -1:
+			err(1, "put");
+		default:
+			abort();
+			break;
+		}
+	}
+	(void)fflush(stdout);
+	exit(0);
+}
+
+/*
+ * normalize whitespace in the original line and place a new string
+ * with whitespace converted to a single space in compline. If the line
+ * contains just comments, we preserve them. If it contains data and
+ * comments, we kill the comments. Return 1 if the line had actual
+ * contents, or 0 if it was just a comment without alphanumeric characters.
+ */
+static int
+comp(const char *origline, char **compline, size_t *len)
+{
+	const unsigned char *p;
+	unsigned char *q;
+	char *cline;
+	size_t l = *len, complen;
+	int hasalnum, iscomment;
+
+	/* Eat leading space */
+	for (p = (const unsigned char *)origline; l && *p && isspace(*p);
+	    p++, l--)
+		continue;
+	if ((cline = malloc(l + 1)) == NULL)
+		err(1, "Cannot allocate %zu bytes", l + 1);
+	(void)memcpy(cline, p, l);
+	cline[l] = '\0';
+	if (*cline == '\0')
+		return 0;
+
+	complen = 0;
+	hasalnum = 0;
+	iscomment = 0;
+
+	for (q = (unsigned char *)cline; l && *p; p++, l--) {
+		if (isspace(*p)) {
+			if (complen && isspace(q[-1]))
+				continue;
+			*q++ = ' ';
+			complen++;
+		} else {
+			if (!iscomment && *p == '#') {
+				if (hasalnum)
+					break;
+				iscomment = 1;
+			} else
+				hasalnum |= isalnum(*p);
+			*q++ = *p;
+			complen++;
+		}
+	}
+
+	/* Eat trailing space */
+	while (complen && isspace(q[-1])) {
+		--q;
+		--complen;
+	}
+	*q = '\0';
+	*compline = cline;
+	*len = complen;
+	return hasalnum;
+}