>From ecba7a9f5ee5169c33db9cb83a99ba7ebc46e10f Mon Sep 17 00:00:00 2001
From: Eygene Ryabinkin <rea-fbsd@codelabs.ru>
Date: Sat, 12 Apr 2008 21:43:44 +0400
Subject: [PATCH] rc.d/resolv: implement creation of resolv.conf from rc.conf variables.

Two new variables for rc.conf:
- resolv_domain, the name of the default DNS domain,
- resolv_nameservers, the list of the name servers
  separated by ',' or ' '.

If there are no kenv variables dhcp.domain-name-servers and
dhcp.domain-name, but any of rc.conf variables mentioned above
are set, then /etc/resolv.conf will be built from the contents
of these variables.

Signed-off-by: Eygene Ryabinkin <rea-fbsd@codelabs.ru>
---
 etc/defaults/rc.conf     |    6 ++++++
 etc/rc.d/resolv          |   35 +++++++++++++++++++++++++----------
 share/man/man5/rc.conf.5 |   10 ++++++++++
 3 files changed, 41 insertions(+), 10 deletions(-)

diff --git a/etc/defaults/rc.conf b/etc/defaults/rc.conf
index 1a23b72..cd9c142 100644
--- a/etc/defaults/rc.conf
+++ b/etc/defaults/rc.conf
@@ -237,6 +237,12 @@ named_chroot_autoupdate="YES"	# Automatically install/update chrooted
 named_symlink_enable="YES"	# Symlink the chrooted pid file
 
 #
+# resolv.  Build /etc/resolv.conf programmatically.
+#
+resolv_domain=""		# DNS domain we're in.
+resolv_nameservers=""		# List of DNS server IPs, separated by comma or space.
+
+#
 # kerberos. Do not run the admin daemons on slave servers
 #
 kerberos5_server_enable="NO"	# Run a kerberos 5 master server (or NO).
diff --git a/etc/rc.d/resolv b/etc/rc.d/resolv
index 00c2f49..3f36a0c 100644
--- a/etc/rc.d/resolv
+++ b/etc/rc.d/resolv
@@ -38,20 +38,35 @@ stop_cmd=':'
 
 load_rc_config $name
 
+# Helper that echoes the contents of the resolv.conf to the stdout.
+# Arguments:
+# 1. domain name,
+# 2. list of name servers separated by ',' or ' '.
+# Either argument can be empty.  If so, it won't be included to the output.
+
+build_resolv () {
+	if [ -n "$1" ]; then
+		echo domain "$1"
+	fi
+
+	set -- "$2"
+	for ns in `IFS=', '; echo $*`; do
+		echo nameserver $ns
+	done
+}
+
 # if the info is available via dhcp/kenv
 # build the resolv.conf
 #
 if [ ! -e /etc/resolv.conf -a \
     -n "`/bin/kenv dhcp.domain-name-servers 2> /dev/null`" ]; then
-	> /etc/resolv.conf
-
-	if [ -n "`/bin/kenv dhcp.domain-name 2> /dev/null`" ]; then
-		echo domain `/bin/kenv dhcp.domain-name` > /etc/resolv.conf
-	fi
-
-	set -- `/bin/kenv dhcp.domain-name-servers`
-	for ns in `IFS=','; echo $*`; do
-		echo nameserver $ns >> /etc/resolv.conf;
-	done
+	build_resolv \
+	    "`/bin/kenv dhcp.domain-name 2> /dev/null`" \
+	    "`/bin/kenv dhcp.domain-name-servers`" \
+	    > /etc/resolv.conf
+elif [ -n "${resolv_domain}" -o -n "${resolv_nameservers}" ]; then
+	build_resolv \
+	    "${resolv_domain}" "${resolv_nameservers}" \
+	    > /etc/resolv.conf
 fi
 
diff --git a/share/man/man5/rc.conf.5 b/share/man/man5/rc.conf.5
index a900d6a..af5d61f 100644
--- a/share/man/man5/rc.conf.5
+++ b/share/man/man5/rc.conf.5
@@ -1602,6 +1602,16 @@ daemon's PID file
 into the
 .Xr chroot 8
 environment.
+.It Va resolv_domain
+.Pq Vt str
+name of the local domain.
+Used for the programmatical building of
+.Pa /etc/resolv.conf .
+.It Va resolv_nameservers
+.Pq Vt str
+comma- or space-separated list of nameservers.
+Used for the programmatical building of
+.Pa /etc/resolv.conf .
 .It Va kerberos5_server_enable
 .Pq Vt bool
 Set to
-- 
1.5.3.8