#!/bin/sh
# /etc/ppp ip-goingdown -ci "-vD" -s "ip-up ip-down" -- \
# ip-goingdown -- This script handles ip-(up|goingdown|down) for ppp|diald
# Copyright (C) 2003 by Richard Hawes <rhawes@dma.org>
# This is free software; see the GNU General Public License version 2
# or later for copying conditions.  There is NO warranty.
# $Revision: 1.18 $
# latest version: www.dma.org/~rhawes/programs/ip-goingdown


# check /tmp/ip-goingdown.errors for fatal errors

# USAGE: make symbolic links to this program
# in /etc/ppp/ for ip-up ip-down
#
# ip-goingdown can be called from diald or a script such as poff
# the first parameter has to be the interface name

#	NAME SPACE
# unexported variables begin with underscore or single letter prefix
# functions and variables in sourced files should begin with another prefix
# to avoid conflicts with future versions


exec 3<>/dev/null;

p_init() {
	SCRIPTNAME="$1";
	VARNAME="$2";
	eval export PARAM_$2=\"$3\";

	# source ip-conf
	_if_test -f . "$_ETC/ip-conf"||:;

	TIME_STAMP="$TMPDIR/${IFNAME}.goingdown";
	PPP_EXPORTS="$TMPDIR/${IFNAME}.exports";

	hash $_CMD_LIST||{ hash $_CMD_LIST&>/tmp/ip-goingdown.errors;}||exit;
}

p_log() { logger $_LOG_OPT -t "$SCRIPTNAME[$$]";}

p_param() {
	export PPP_IPPARAM="$6" PPP_TTYNAME=`basename "$DEVICE"`;
	#the other parameters are in the environment
	# $1 == IFNAME
	# $2 == DEVICE
	# $3 == SPEED
	# $4 == IPLOCAL
	# $5 == IPREMOTE
	# but because scripts use these variables . . .
	export PPP_IFACE="$1" PPP_TTY="$2" PPP_SPEED="$3"
	export PPP_LOCAL="$4" PPP_REMOTE="$5"
}

r_pts() {
	export SCRIPTNAME VARNAME;
	eval "$1";
	eval "$2";
	_if_source "$3"||:;
	_if_source "${3}.${PPP_TTYNAME}"||:;
	_if_test -d run-parts "${4}.${PPP_TTYNAME}"||
	_if_test -d run-parts "${4}"
	_if_source "$5"||:;
	_if_source "${5}.${PPP_TTYNAME}"||:;
	eval "$6";
	eval "$7";
}

r_parts() {
	eval _if_unempty renice \"\$_NICE_$1_${PPP_TTYNAME}\" $$||
	eval _if_unempty renice \"\$_NICE_$1\" $$;
	eval r_pts \"\$E_PRE$1\" \"\$E_PRE$1_${PPP_TTYNAME}\" \"\$S_PRE$1\" \
	\"\$D_$1\" \"\$S_POST$1\" \"\$E_POST$1\" \"\$E_POST$1_${PPP_TTYNAME}\"
}

r_pts_goingdown() {
	[ -f "$TIME_STAMP" ]&&[ "$PPP_EXPORTS" -ot "$TIME_STAMP" ]||
	{
		touch "$TIME_STAMP";
		r_parts GOINGDOWN;
	}
}

r_pts_up() {
	_if_test -f "mv -vfb" "$TMPDIR" "${TMPDIR}.orig.$$"||:;
	_if_test '! -d' "mkdir -vp" "$TMPDIR"||:;
	export IP_UP_PID=$$;
	# save exports for goingdown
	export -p >"$PPP_EXPORTS";
	# give kernel time to set up routes
	eval _if_unempty sleep \"\$_DELAY_${PPP_TTYNAME}\"||
	eval _if_unempty sleep \"\$_DELAY\";
	r_parts UP;
}

# functions that could be used in ip-conf
_if_test() { [ $1 "$3" ]&&{ shift; eval "$@";};}
_if_source() { [ -f "$1" ]&&. $1;}
_if_unempty() { [ "$2" ]&&"$@";}

_ETC=/etc/ppp;
# variables that could be changed in ip-conf
_CMD_LIST="echo grep kill logger ls renice run-parts sleep touch";
_DELAY=;
_LOG_OPT="-p user.debug";
_NICE_GOINGDOWN=;
_NICE_DOWN=;
_NICE_UP=;
D_DOWN="$_ETC/ip-down.d";
D_GOINGDOWN="$_ETC/ip-goingdown.d";
D_UP="$_ETC/ip-up.d";
E_PREDOWN=":";
E_PREGOINGDOWN=":";
E_PREUP=":";
E_POSTDOWN=":";
E_POSTGOINGDOWN=":";
E_POSTUP=":";
S_PREDOWN="$_ETC/ip-predown";
S_PREGOINGDOWN="$_ETC/ip-pregoingdown";
S_PREUP="$_ETC/ip-preup";
S_POSTDOWN="$_ETC/ip-postdown";
S_POSTGOINGDOWN="$_ETC/ip-postgoingdown";
S_POSTUP="$_ETC/ip-postup";
PATH=/usr/local/sbin:/usr/sbin:/sbin:/usr/local/bin:/usr/bin:/bin;
TMPDIR=/var/tmp/ppp;
export PATH TMPDIR;

#base names of symbolic links to this program
P_UP="ip-up";
P_DOWN="ip-down";
P_GOINGDOWN="ip-goingdown";

case "$0" in
*"$P_UP")
	p_param "$@";
	p_init "$P_UP" IP_UP "$*";
	r_pts_up 2>&1 | p_log;;
*"$P_GOINGDOWN")
	IFNAME="$1";
	p_init "$P_GOINGDOWN" IP_GOINGDOWN "$*";
	{
		. "$PPP_EXPORTS";
		# send ip-up HUP if it is still running
		kill -0 $IP_UP_PID 2>&3 &&
		kill -HUP $IP_UP_PID;
		r_pts_goingdown;
	} 2>&1 | p_log;;
*"$P_DOWN")
	p_param "$@";
	p_init "$P_DOWN" IP_DOWN "$*";
	{
		r_pts_goingdown;
		r_parts DOWN;
	} 2>&1 | p_log;;
*) echo "called with invalid name: $0" >&2; exit 1;;
esac