/etc/rc.d/defaultroute currently bails immediately if all interfaces

set to use DHCP have no carrier.  This can cause grief as it may take
some time for link to be established, and defaultroute may terminate
before this happens.

Introduce a defaultroute_carrier_delay variable and then wait that long
in defaultroute before bailing if no interfaces have carrier.  With the
default settings defaultroute will wait for five seconds for this, and
the original 30 second wait for a default route to appear is unchanged.
Note that there is in discussion an alternative approach to the broader
problem of waiting for DHCP-configured routes.  However, this change
addresses a real problem in the current defaultroute script.

Discussed on:	freebsd-rc@

etc/rc.d/defaultroute

@@ -1,6 +1,6 @@
 #!/bin/sh
 #
-# Wait for the default route to be up
+# Wait for the default route to be up if DHCP is in use
 #
 # $FreeBSD$
 #
@@ -16,9 +16,23 @@ name="defaultroute"
 start_cmd="defaultroute_start"
 stop_cmd=":"
 
+# Does any interface have a carrier?
+defaultroute_carrier()
+{
+	local carrier nocarrier
+
+	carrier=1
+	for _if in ${dhcp_interfaces}; do
+		output=`/sbin/ifconfig ${_if}`
+		nocarrier=`expr "${output}" : '.*[[:blank:]]status: \(no carrier\)'`
+		[ -z "${nocarrier}" ] && carrier=0
+	done
+	return ${carrier}
+}
+
 defaultroute_start()
 {
-	local output carrier nocarrier nl
+	local nl waited
 
 	afexists inet || return 0
 
@@ -26,35 +40,30 @@ defaultroute_start()
 	# if none of the dhcp interfaces is plugged in.
 	dhcp_interfaces=`list_net_interfaces dhcp`
 	[ -z "${dhcp_interfaces}" ] && return
-	carrier=false
-	for _if in ${dhcp_interfaces}; do
-		output=`/sbin/ifconfig ${_if}`
-		nocarrier=`expr "${output}" : '.*[[:blank:]]status: \(no carrier\)'`
-		[ -z "${nocarrier}" ] && carrier=true
-	done
-	if ! ${carrier}; then
-		return
-	fi
 
 	# Wait for a default route
-	delay=${defaultroute_delay}
-	while [ ${delay} -gt 0 ]; do
+	waited=0
+	while [ ${waited} -lt ${defaultroute_delay} ]; do
 		defif=`get_default_if -inet`
 		if [ -n "${defif}" ]; then
-			if [ ${delay} -ne ${defaultroute_delay} ]; then
+			if [ ${waited} -ne 0 ]; then
 				echo -n "($defif)"
 				nl=1
 			fi
 			break
 		fi
-		if [ ${delay} -eq ${defaultroute_delay} ]; then
-			echo -n "Waiting ${delay}s for the default route interface: "
+		if [ ${waited} -eq 0 ]; then
+			echo -n "Waiting ${defaultroute_delay}s for the default route interface: "
 		else
 			echo -n .
 		fi
+		if [ ${waited} -eq ${defaultroute_carrier_delay} ] && ! defaultroute_carrier; then
+			echo -n "(no carrier)"
+			break
+		fi
 		nl=1
 		sleep 1
-		delay=$(($delay - 1))
+		waited=$(($waited + 1))
 	done
 
 	[ -n "$nl" ] && echo