[PATCH] busybox: Update udhcpc.script for DHCPv6

[Bernhard Reutner-Fischer]

On 18 June 2018 04:09:55 CEST, Samuel Mendoza-Jonas <sam at mendozajonas.com> wrote:
>udhcpc6 will call the default script with the address set in the "ipv6"
>variable. Set "ip" to this address if present.
>
>Also from Rob, if handling a DHCPv6 address wait a moment for the IPv6
>route to be configured; this doesn't come from DHCPv6 but rather the
>IPv6 Router Advertisement (RA).
>
>(wait for IPv6 route)
>From: Robert Lippert <rlippert at google.com>
>Signed-off-by: Samuel Mendoza-Jonas <sam at mendozajonas.com>
>---
> package/busybox/udhcpc.script | 14 ++++++++++++++
> 1 file changed, 14 insertions(+)
>
>diff --git a/package/busybox/udhcpc.script
>b/package/busybox/udhcpc.script
>index ad110d3a7f..9613d00e81 100755
>--- a/package/busybox/udhcpc.script
>+++ b/package/busybox/udhcpc.script
>@@ -8,6 +8,16 @@ RESOLV_CONF="/etc/resolv.conf"
> [ -e $RESOLV_CONF ] || touch $RESOLV_CONF
> [ -n "$broadcast" ] && BROADCAST="broadcast $broadcast"
> [ -n "$subnet" ] && NETMASK="netmask $subnet"
>+[ -n "$ipv6" ] && ip="$ipv6/128"
>+
>+wait_for_ipv6_default_route() {
>+	attempts=10
>+	while [ $attempts != 0 ] && [ -z "$(ip -6 route list | grep default)"
>] ; do
>+		sleep 1
>+		let attempts="$attempts-1"

No non-portable extensions please.
attempts=$(($attempts-1))

>+	done
>+	[ $attempts == 0 ] && echo "failed to get default ipv6 route"

the double equal operator is removed from test(1).
Please use the shorter and correct equality operator.

Thanks.

>+}
> 
> case "$1" in
> 	deconfig)
>@@ -37,6 +47,10 @@ case "$1" in
> 			/usr/sbin/avahi-autoipd -k $interface
> 		fi
> 		/sbin/ifconfig $interface $ip $BROADCAST $NETMASK
>+		if [ -n "$ipv6" ] ; then
>+			echo "waiting for default ipv6 route set"
>+			wait_for_ipv6_default_route
>+		fi
> 
> 		if [ -n "$router" ] ; then
> 			echo "deleting routers"