| Current File : //usr/lib/udev/ifupdown-hotplug |
#!/bin/sh -e
#
# run /sbin/{ifup,ifdown} with the --allow=hotplug option.
#
PATH='/sbin:/bin:/usr/sbin:/usr/bin'
if [ -x /usr/bin/logger ]; then
LOGGER=/usr/bin/logger
elif [ -x /bin/logger ]; then
LOGGER=/bin/logger
else
unset LOGGER
fi
# for diagnostics
if [ -t 1 -a -z "$LOGGER" ] || [ ! -e '/dev/log' ]; then
mesg() {
echo "$@" >&2
}
elif [ -t 1 ]; then
mesg() {
echo "$@"
$LOGGER -t "${0##*/}[$$]" "$@"
}
else
mesg() {
$LOGGER -t "${0##*/}[$$]" "$@"
}
fi
if [ -z "$INTERFACE" ]; then
mesg "Bad ifupdown udev helper invocation: \$INTERFACE is not set"
exit 1
fi
check_program() {
[ -x $1 ] && return 0
mesg "ERROR: $1 not found. You need to install the ifupdown package."
mesg "ifupdown udev helper $ACTION event for $INTERFACE not handled."
exit 1
}
wait_for_interface() {
local interface=$1
local state
while :; do
read state /sys/class/net/$interface/operstate 2>/dev/null || true
if [ "$state" != down ]; then
return 0
fi
sleep 1
done
}
net_ifup() {
check_program /sbin/ifup
# exit if the interface is not configured as allow-hotplug
TARGET_IFACE=$(/sbin/ifquery --allow hotplug -l "$INTERFACE" || true)
if [ -z "$TARGET_IFACE" ]; then
TARGET_IFACE=$(/sbin/ifquery --allow auto -l "$INTERFACE" || true)
fi
if [ -z "$TARGET_IFACE" ]; then
exit 0
fi
if [ -d /run/systemd/system ]; then
exec systemctl --no-block start $(systemd-escape --template ifup@.service $TARGET_IFACE)
fi
wait_for_interface lo
exec ifup --allow=hotplug $INTERFACE
}
net_ifdown() {
check_program /sbin/ifdown
# systemd will automatically ifdown the interface on device
# removal by binding the instanced service to the network device
if [ -d /run/systemd/system ]; then
exit 0
fi
exec ifdown --allow=hotplug $INTERFACE
}
do_everything() {
case "$ACTION" in
add)
# these interfaces generate hotplug events *after* they are brought up
case $INTERFACE in
ppp*|ippp*|isdn*|plip*|lo|irda*|ipsec*)
exit 0 ;;
esac
net_ifup
;;
remove)
# the pppd persist option may have been used, so it should not be killed
case $INTERFACE in
ppp*)
exit 0 ;;
esac
net_ifdown
;;
*)
mesg "NET $ACTION event not supported"
exit 1
;;
esac
}
# under systemd we don't do synchronous operations, so we can run in the
# foreground; we also need to, as forked children get killed right away under
# systemd
if [ -d /run/systemd/system ]; then
do_everything
else
# under sysvinit we need to fork as we start the long-running
# "ifup". but there, forked processes won't get killed.
# When udev_log="debug" stdout and stderr are pipes connected to udevd.
# They need to be closed or udevd will wait for this process which will
# deadlock with udevsettle until the timeout.
exec > /dev/null 2> /dev/null
do_everything &
fi