#! /bin/sh
#
# Copyright (c) 2002 Gordon Tetlow. All rights reserved.
# Copyright (c) 2012 Sandvine Incorporated. All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
# $FreeBSD: stable/11/sbin/reboot/nextboot.sh 297980 2016-04-14 18:03:55Z markj $

setglobal append = '"NO'"
setglobal delete = '"NO'"
setglobal kenv = ''
setglobal force = '"NO'"
setglobal nextboot_file = '"/boot/nextboot.conf'"

proc add_kenv
{
	var var = '', value = ''

	set var = $1
	# strip literal quotes if passed in
	set value = $(2%\"*)
	set value = $(value#*\")

	if test -n $(kenv) {
		setglobal kenv = ""$(kenv)
""
	}
	setglobal kenv = ""$(kenv)$(var)=\"$(value)"\""
}

proc display_usage {
	cat << """
Usage: nextboot [-af] [-e variable=value] [-k kernel] [-o options]
       nextboot -D
"""
}

while getopts "aDe:fk:o:" argument {
	match $(argument) {
	with a
		setglobal append = '"YES'"
		
	with D
		setglobal delete = '"YES'"
		
	with e
		setglobal var = $(OPTARG%%=*)
		setglobal value = $(OPTARG#*=)
		if test -z $var -o -z $value {
			display_usage
			exit 1
		}
		add_kenv $var $value
		
	with f
		setglobal force = '"YES'"
		
	with k
		setglobal kernel = $(OPTARG)
		add_kenv kernel $kernel
		
	with o
		add_kenv kernel_options $(OPTARG)
		
	with *
		display_usage
		exit 1
		
	}
}

if test $(delete) = "YES" {
	rm -f $(nextboot_file)
	exit 0
}

if test -z $(kenv) {
	display_usage
	exit 1
}

if test -n $(kernel) -a $(force) = "NO" -a ! -d /boot/$(kernel) {
	echo "Error: /boot/$(kernel) doesn't exist. Use -f to override."
	exit 1
}

df -Tn "/boot/" !2 >/dev/null | while read _fs _type _other {
	test "zfs" = $(_type) || continue
	cat !1 > !2 << """
WARNING: loader(8) has only R/O support for ZFS
nextboot.conf will NOT be reset in case of kernel boot failure
"""
}

set -e

setglobal nextboot_tmp = $[mktemp $[dirname $(nextboot_file)]/nextboot.XXXXXX]

if test $(append) = "YES" -a -f $(nextboot_file) {
	cp -f $(nextboot_file) $(nextboot_tmp)
}

cat >> $(nextboot_tmp) << """
nextboot_enable="YES"
$kenv
"""

fsync $(nextboot_tmp)

mv $(nextboot_tmp) $(nextboot_file)