#!@BASH_SHELL@
#
# Copyright (c) 2014 David Vossel <davidvossel@gmail.com>
#                    All Rights Reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of version 2 of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it would be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
#
# Further, this software is distributed without any warranty that it is
# free of the rightful claim of any third person regarding infringement
# or the like.  Any license provided herein, whether implied or
# otherwise, applies only to this software file.  Patent licenses, if
# any, provided herein do not apply to combinations of this program with
# other software, or any other product whatsoever.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write the Free Software Foundation,
# Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
#

#######################################################################
# Initialization:

: ${OCF_FUNCTIONS_DIR=${OCF_ROOT}/lib/heartbeat}
. ${OCF_FUNCTIONS_DIR}/ocf-shellfuncs
. ${OCF_FUNCTIONS_DIR}/ocf-directories

# Parameter defaults

OCF_RESKEY_source_host_default=""
OCF_RESKEY_notify_args_default=""

: ${OCF_RESKEY_source_host=${OCF_RESKEY_source_host_default}}
: ${OCF_RESKEY_notify_args=${OCF_RESKEY_notify_args_default}}

#######################################################################

sbindir=$HA_SBIN_DIR
if [ -z "$sbindir" ]; then
	sbindir=/usr/sbin
fi

SELINUX_ENABLED=-1

NFSNOTIFY_TMP_DIR="${HA_RSCTMP}/nfsnotify_${OCF_RESOURCE_INSTANCE}/"
HA_STATD_PIDFILE="$NFSNOTIFY_TMP_DIR/rpc.statd_${OCF_RESOURCE_INSTANCE}.pid"
HA_STATD_PIDFILE_PREV="$NFSNOTIFY_TMP_DIR/rpc.statd_${OCF_RESOURCE_INSTANCE}.pid.prev"
STATD_PATH="/var/lib/nfs/statd"
SM_NOTIFY_BINARY="${sbindir}/sm-notify"
IS_RENOTIFY=0

meta_data() {
	cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="nfsnotify" version="1.0">
<version>1.0</version>

<longdesc lang="en">
This agent sends NFSv3 reboot notifications to clients which informs clients to reclaim locks.
</longdesc>
<shortdesc lang="en">sm-notify reboot notifications</shortdesc>

<parameters>

<parameter name="source_host" unique="0" required="0">
<longdesc lang="en">
Comma separated list of floating IP addresses or host names that clients use
to access the nfs service.  This will be used to set the source address and
mon_name of the SN_NOTIFY reboot notifications.
</longdesc>
<shortdesc lang="en">source IP addresses</shortdesc>
<content type="string" default="${OCF_RESKEY_source_host_default}" />
</parameter>

<parameter name="notify_args" unique="0" required="0">
<longdesc lang="en">
Additional arguments to send to the sm-notify command. By default
this agent will always set sm-notify's '-f' option.  When the
source_host option is set, the '-v' option will be used automatically
to set the proper source address. Any additional sm-notify arguments
set with this option will be used in addition to the previous default
arguments.
</longdesc>
<shortdesc lang="en">sm-notify arguments</shortdesc>
<content type="string" default="${OCF_RESKEY_notify_args_default}" />
</parameter>

</parameters>

<actions>
<action name="start"        timeout="90s" />
<action name="stop"         timeout="90s" />
<action name="monitor"      timeout="90s" interval="30s" depth="0" />
<action name="reload"       timeout="90s" />
<action name="meta-data"    timeout="10s" />
<action name="validate-all"   timeout="20s" />
</actions>
</resource-agent>
END
}

v3notify_usage()
{
	cat <<END
usage: $0 {start|stop|monitor|validate-all|meta-data}

Expects to have a fully populated OCF RA-compliant environment set.
END
}

v3notify_validate()
{
	# check_binary will exit with OCF_ERR_INSTALLED when binary is missing
	check_binary "$SM_NOTIFY_BINARY"
	check_binary "pgrep"
	check_binary "killall"

	return $OCF_SUCCESS
}

killall_smnotify()
{
	# killall sm-notify 
	killall -TERM $SM_NOTIFY_BINARY > /dev/null 2>&1
	if [ $? -eq 0 ]; then
		# it is useful to know if sm-notify processes were actually left around
		# or not during the stop/start operation. Whether this condition is true
		# or false does not indicate a failure. It does indicate that 
		# there are probably some unresponsive nfs clients out there that are keeping
		# the sm-notify processes retrying.
		ocf_log info "previous sm-notify processes terminated before $__OCF_ACTION action."
	fi
}

v3notify_stop()
{
	killall_smnotify

	rm -f $HA_STATD_PIDFILE_PREV > /dev/null 2>&1
	mv $HA_STATD_PIDFILE $HA_STATD_PIDFILE_PREV > /dev/null 2>&1

	return $OCF_SUCCESS
}

check_statd_pidfile()
{
	local binary="rpc.statd"
	local pidfile="$HA_STATD_PIDFILE"

	ocf_log debug "Checking status for ${binary}."
	if [ -e "$pidfile" ]; then
		cat /proc/$(cat $pidfile)/cmdline 2>/dev/null | grep -a "${binary}" > /dev/null 2>&1
		if [ $? -eq 0 ]; then
			return $OCF_SUCCESS
		fi

		ocf_exit_reason "$(cat $pidfile) for $binary is no longer running, sm-notify needs to re-notify clients"
		return $OCF_ERR_GENERIC
	fi

	# if we don't have a pid file for rpc.statd, we have not yet sent the notifications
	return $OCF_NOT_RUNNING
}

write_statd_pid()
{
	local binary="rpc.statd"
	local pidfile="$HA_STATD_PIDFILE"
	local pid

	pid=$(pgrep ${binary})
	case $? in
		0)
			ocf_log info "PID file (pid:${pid} at $pidfile) created for ${binary}."
			mkdir -p $(dirname $pidfile)
			echo "$pid" > $pidfile
			return $OCF_SUCCESS;;
		1)
			rm -f "$pidfile" > /dev/null 2>&1 
			ocf_log info "$binary is not running"
			return $OCF_NOT_RUNNING;;
		*)
			rm -f "$pidfile" > /dev/null 2>&1 
		  	ocf_exit_reason "Error encountered detecting pid status of $binary"
			return $OCF_ERR_GENERIC;;
	esac
}

copy_statd()
{
	local src=$1
	local dest=$2

	if ! [ -d "$dest" ]; then
		mkdir -p "$dest"
	fi

	cp -rpfn $src/sm $src/sm.bak $src/state $dest > /dev/null 2>&1

	# make sure folder ownership and selinux lables stay consistent
	# When using nfsnotify resources on the debian system, the statd user replaces the rpcuser user 
	local rpcuser_exist=`grep rpcuser /etc/passwd` 
	if  [ -z "$rpcuser_exist" ];then 
		[ -n "`id -u statd`" ] && [ -n "`id -g statd`" ] && chown statd "$dest" 
	else 
		[ -n "`id -u rpcuser`" ] && [ -n "`id -g rpcuser`" ] && chown rpcuser.rpcuser "$dest" 
	fi

	[ $SELINUX_ENABLED -eq 0 ] && chcon -R "$SELINUX_LABEL" "$dest"
}

v3notify_start()
{
	local rc=$OCF_SUCCESS
	local cur_statd
	local statd_backup
	local is_renotify=0

	# monitor, see if we need to notify or not
	v3notify_monitor
	if [ $? -eq 0 ]; then
		return $OCF_SUCCESS
	fi

	# kill off any other sm-notify processes that might already be running.
	killall_smnotify

	# record the pid of rpc.statd. if this pid ever changes, we have to re-notify
	write_statd_pid
	rc=$?
	if [ $rc -ne 0 ]; then
		return $rc
	fi

	# if the last time we ran nfs-notify, it was with the same statd process,
	# consider this a re-notification. During re-notifications we do not let the
	# sm-notify binary have access to the real statd directory.
	if [ "$(cat $HA_STATD_PIDFILE)" = "$(cat $HA_STATD_PIDFILE_PREV 2>/dev/null)" ]; then
		ocf_log info "Renotifying clients"
		is_renotify=1
	fi

	statd_backup="$STATD_PATH/nfsnotify.bu"
	copy_statd "$STATD_PATH" "$statd_backup"

	if [ -z "$OCF_RESKEY_source_host" ]; then
		if [ "$is_renotify" -eq 0 ]; then
			cur_statd="$STATD_PATH"
		else 
			cur_statd="$statd_backup"
		fi
		ocf_log info "sending notifications on default source address."
		$SM_NOTIFY_BINARY -f $OCF_RESKEY_notify_args -P $cur_statd
		if [ $? -ne 0 ]; then
			ocf_exit_reason "sm-notify execution failed, view syslog for more information"
			return $OCF_ERR_GENERIC
		fi
		
		return $OCF_SUCCESS
	fi

	# do sm-notify for each ip
	for ip in `echo ${OCF_RESKEY_source_host} | sed 's/,/ /g'`; do

		# have the first sm-notify use the actual statd directory so the
		# notify list can be managed properly.
		if [ "$is_renotify" -eq 0 ]; then
			cur_statd="$STATD_PATH"
			# everything after the first notify we are considering a renotification
			# which means we don't use the real statd directory. 
			is_renotify=1
		else 
			# use our copied statd directory for the remaining ip addresses
			cur_statd="$STATD_PATH/nfsnotify_${OCF_RESOURCE_INSTANCE}_${ip}"
			copy_statd "$statd_backup" "$cur_statd"
		fi

		ocf_log info "sending notifications with source address $ip"
		$SM_NOTIFY_BINARY -f $OCF_RESKEY_notify_args -v $ip -P "$cur_statd"
		if [ $? -ne 0 ]; then
			ocf_exit_reason "sm-notify with source host set to [ $ip ] failed. view syslog for more information"
			return $OCF_ERR_GENERIC
		fi
	done

	return $OCF_SUCCESS
}

v3notify_monitor()
{
	# verify rpc.statd is up, and that the rpc.statd pid is the same one we
	# found during the start. otherwise rpc.statd recovered and we need to notify
	# again.
	check_statd_pidfile
}

case $__OCF_ACTION in
	meta-data)   meta_data
		exit $OCF_SUCCESS;;
	usage|help)    v3notify_usage
		exit $OCF_SUCCESS;;
	*)
		;;
esac

which restorecon > /dev/null 2>&1 && selinuxenabled
SELINUX_ENABLED=$?
if [ $SELINUX_ENABLED -eq 0 ]; then
	export SELINUX_LABEL="$(ls -dZ $STATD_PATH | grep -o '\S\+:\S\+:\S\+')"
fi

case $__OCF_ACTION in
	start)         v3notify_start;;
	stop)          v3notify_stop;;
	monitor)       v3notify_monitor;;
	validate-all)  v3notify_validate;;
	*)             v3notify_usage
	               exit $OCF_ERR_UNIMPLEMENTED;;
esac

rc=$?
ocf_log debug "${OCF_RESOURCE_INSTANCE} $__OCF_ACTION : $rc"
exit $rc