#!/bin/bash
#
# 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

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

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

<longdesc lang="en">
This agent manages the clvmd daemon.
</longdesc>
<shortdesc lang="en">clvmd</shortdesc>

<parameters>
<parameter name="with_cmirrord" unique="0" required="0">
<longdesc lang="en">
Start with cmirrord (cluster mirror log daemon).
</longdesc>
<shortdesc lang="en">activate cmirrord</shortdesc>
<content type="boolean" default="false" />
</parameter>

<parameter name="daemon_options" unique="0">
<longdesc lang="en">
Options to clvmd. Refer to clvmd.8 for detailed descriptions.
</longdesc>
<shortdesc lang="en">Daemon Options</shortdesc>
<content type="string" default="-d0"/>
</parameter>

<parameter name="activate_vgs" unique="0">
<longdesc lang="en">
Whether or not to activate all cluster volume groups after starting
the clvmd or not. Note that clustered volume groups will always be
deactivated before the clvmd stops regardless of what this option
is set to.
</longdesc>
<shortdesc lang="en">Activate volume groups</shortdesc>
<content type="boolean" default="true"/>
</parameter>

</parameters>

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

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

: ${OCF_RESKEY_daemon_options:="-d0"}
: ${OCF_RESKEY_activate_vgs:="true"}

sbindir=$HA_SBIN_DIR
if [ -z $sbindir ]; then
	sbindir=/usr/sbin
fi
DAEMON="clvmd"
CMIRROR="cmirrord"
DAEMON_PATH="${sbindir}/clvmd"
CMIRROR_PATH="${sbindir}/cmirrord"
LVMCONF="${sbindir}/lvmconf"
LOCK_FILE="/var/lock/subsys/$DAEMON"

# attempt to detect where the vg tools are located
# for some reason this isn't consistent with sbindir
# in some distros.
vgtoolsdir=$(dirname $(which vgchange 2> /dev/null) 2> /dev/null)
if [ -z "$vgtoolsdir" ]; then
       vgtoolsdir="$sbindir"
fi

LVM_VGCHANGE=${vgtoolsdir}/vgchange
LVM_VGDISPLAY=${vgtoolsdir}/vgdisplay
LVM_VGSCAN=${vgtoolsdir}/vgscan

# Leaving this in for legacy. We do not want to advertize
# the abilty to set options in the systconfig exists, we want
# to expand the OCF style options as necessary instead.
[ -f /etc/sysconfig/cluster ] && . /etc/sysconfig/cluster
[ -f /etc/sysconfig/$DAEMON ] && . /etc/sysconfig/$DAEMON

CLVMD_TIMEOUT="90"
if [ -n "$OCF_RESKEY_CRM_meta_timeout" ]; then
	CLVMD_TIMEOUT=$(($OCF_RESKEY_CRM_meta_timeout/1000))
fi

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

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

clvmd_validate()
{
	# check_binary will exit with OCF_ERR_INSTALLED
	# when binary is missing
	check_binary "pgrep"
	check_binary $DAEMON_PATH
	if ocf_is_true $OCF_RESKEY_with_cmirrord; then
		check_binary $CMIRROR_PATH
	fi

	if [ "$__OCF_ACTION" != "monitor" ]; then
		check_binary "killall"
		check_binary $LVM_VGCHANGE
		check_binary $LVM_VGDISPLAY
		check_binary $LVM_VGSCAN
	fi

	# Future validation checks here.
	return $OCF_SUCCESS
}

check_process()
{
	local binary=$1
	local pidfile="${HA_RSCTMP}/${binary}-${OCF_RESOURCE_INSTANCE}.pid"
	local pid

	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
			# shortcut without requiring pgrep to search through all procs
			return $OCF_SUCCESS
		fi
	fi

	pid=$(pgrep ${binary})
	case $? in
		0)
			ocf_log info "PID file (pid:${pid} at $pidfile) created for ${binary}."
			echo "$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
}

clvmd_status()
{
	local rc
	local mirror_rc
	clvmd_validate
	if [ $? -ne $OCF_SUCCESS ]; then
		ocf_exit_reason "Unable to monitor, Environment validation failed."
		return $?
	fi

	check_process $DAEMON
	rc=$?
	mirror_rc=$rc

	if ocf_is_true $OCF_RESKEY_with_cmirrord; then
		check_process $CMIRROR
		mirror_rc=$?
	fi

	# If these ever don't match, return error to force recovery
	if [ $mirror_rc -ne $rc ]; then
		return $OCF_ERR_GENERIC
	fi

	return $rc
}

# NOTE: replace this with vgs, once display filter per attr is implemented.
clustered_vgs() {
	${LVM_VGDISPLAY} 2>/dev/null | awk 'BEGIN {RS="VG Name"} {if (/Clustered/) print $1;}'
}

wait_for_process()
{
	local binary=$1
	local timeout=$2
	local count=0

	ocf_log info "Waiting for $binary to exit"
	while [ $count -le $timeout ]; do
		check_process $binary
		if [ $? -eq $OCF_NOT_RUNNING ]; then
			ocf_log info "$binary terminated"
			return $OCF_SUCCESS
		fi
		sleep 1
		count=$((count+1))
	done

	return $OCF_ERR_GENERIC
}

time_left()
{
	local end=$1
	local default=$2
	local now=$SECONDS
	local result=0

	result=$(( $end - $now ))
	if [ $result -lt $default ]; then
		return $default
	fi
	return $result
}

clvmd_stop()
{
	local LVM_VGS
	local rc=$OCF_SUCCESS
	local end=$(( $SECONDS + $CLVMD_TIMEOUT ))

	clvmd_status
	if [ $? -eq $OCF_NOT_RUNNING ]; then
		return $OCF_SUCCESS
	fi

	check_process $DAEMON
	if [ $? -ne $OCF_NOT_RUNNING ]; then
		LVM_VGS="$(clustered_vgs)"

		if [ -n "$LVM_VGS" ]; then
			ocf_log info "Deactivating clustered VG(s):" 
			ocf_run ${LVM_VGCHANGE} -anl $LVM_VGS
			if [ $? -ne 0 ]; then
				ocf_exit_reason "Failed to deactivate volume groups, cluster vglist = $LVM_VGS" 
				return $OCF_ERR_GENERIC
			fi
		fi

		ocf_log info "Signaling $DAEMON to exit"
		killall -TERM $DAEMON
		if [ $? != 0 ]; then
			ocf_exit_reason "Failed to signal -TERM to $DAEMON"
			return $OCF_ERR_GENERIC
		fi

		wait_for_process $DAEMON $CLVMD_TIMEOUT
		rc=$?
		if [ $rc -ne $OCF_SUCCESS ]; then
			ocf_exit_reason "$DAEMON failed to exit"
			return $rc
		fi

		rm -f $LOCK_FILE
	fi

	check_process $CMIRROR
	if [ $? -ne $OCF_NOT_RUNNING ] && ocf_is_true $OCF_RESKEY_with_cmirrord; then
		local timeout
		ocf_log info "Signaling $CMIRROR to exit"
		killall -INT $CMIRROR

		time_left $end 10; timeout=$?
		wait_for_process $CMIRROR $timeout
		rc=$?
		if [ $rc -ne $OCF_SUCCESS ]; then
			killall -KILL $CMIRROR
			time_left $end 10; timeout=$?
			wait_for_process $CMIRROR $(time_left $end 10)
			rc=$?
		fi
	fi

	return $rc
}

start_process()
{
	local binary_path=$1
	local opts=$2

	check_process "$(basename $binary_path)"
	if [ $? -ne $OCF_SUCCESS ]; then
		ocf_log info "Starting $binary_path: "
		ocf_run $binary_path $opts
		rc=$?
		if [ $rc -ne 0 ]; then
			ocf_exit_reason "Failed to launch $binary_path, exit code $rc"
			exit $OCF_ERR_GENERIC
		fi
	fi

	return $OCF_SUCCESS
}

clvmd_activate_all()
{

	if ! ocf_is_true "$OCF_RESKEY_activate_vgs"; then
		ocf_log info "skipping vg activation, activate_vgs is set to $OCF_RESKEY_activate_vgs"
		return $OCF_SUCCESS
	fi
	# Activate all volume groups by leaving the
	# "volume group name" parameter empty
	ocf_run ${LVM_VGCHANGE} -aay
	if [ $? -ne 0 ]; then
		ocf_log info "Failed to activate VG(s):"
		clvmd_stop
		return $OCF_ERR_GENERIC
	fi
	return $OCF_SUCCESS
}

clvmd_start()
{
	local rc=0
	local CLVMDOPTS="-T${CLVMD_TIMEOUT} $OCF_RESKEY_daemon_options"

	clvmd_validate
	if [ $? -ne $OCF_SUCCESS ]; then
		ocf_exit_reason "Unable to start, Environment validation failed."
		return $?
	fi

	clvmd_status
	if [ $? -eq $OCF_SUCCESS ]; then
		ocf_log debug "$DAEMON already started"
		clvmd_activate_all
		return $?;
	fi

	# autoset locking type to clusted when lvmconf tool is available
	if [ -x "$LVMCONF"  ]; then
		$LVMCONF --enable-cluster > /dev/null 2>&1
	fi

	# if either of these fail, script will exit OCF_ERR_GENERIC
	if ocf_is_true $OCF_RESKEY_with_cmirrord; then
		start_process $CMIRROR_PATH
	fi
	start_process $DAEMON_PATH "$CLVMDOPTS"

	# Refresh local cache.
	#
	# It's possible that new PVs were added to this, or other VGs
	# while this node was down. So we run vgscan here to avoid
	# any potential "Missing UUID" messages with subsequent
	# LVM commands.

	# The following step would be better and more informative to the user:
	# 'action "Refreshing VG(s) local cache:" ${LVM_VGSCAN}'
	# but it could show warnings such as:
	# 'clvmd not running on node x-y-z  Unable to obtain global lock.'
	# and the action would be shown as FAILED when in reality it didn't.
	# Ideally vgscan should have a startup mode that would not print
	# unnecessary warnings.

	${LVM_VGSCAN} > /dev/null 2>&1
	touch $LOCK_FILE

	clvmd_activate_all

	clvmd_status
	return $?
}

case $__OCF_ACTION in
	meta-data)   meta_data
		exit $OCF_SUCCESS;;

	start)         clvmd_start;;

	stop)          clvmd_stop;;

	monitor)       clvmd_status;;

	validate-all)  clvmd_validate;;

	usage|help)    clvmd_usage;;

	*)             clvmd_usage
	               exit $OCF_ERR_UNIMPLEMENTED;;
esac

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