#!/bin/sh
#
# Support:      linux-ha@lists.linux-ha.org
# License:      GNU General Public License (GPL)
# 
# EvmsSCC
#      Description: Runs evms_activate in a heartbeat cluster to activate a 
#		    EVMS shared cluster container in the cluster.
#  Original Author: Jo De Baer (jdebaer@novell.com)
# Original Release: 06 Nov 2006
#
# usage: ./EvmsSCC {start|stop|status|monitor|meta-data}
#
# The goal of this resource agent is to provoke the creation of device file
# in /dev/emvs which correspond to EVMS2 volumes that reside in a EVMS2 shared
# cluster container. As such it should be run as a clone resource in the 
# cluster. Logic inside the resource agent will make sure that "evms_activate"
# is run on only one node in the cluster, both at cluster startup time as well
# as when a node joins the cluster.
#
# Typically, resources that need to mount EVMS2 volumes should run after this
# resource agent has finished it's run. As such those resources should be made
# "dependent" on this resource agent by the cluster administrator. An example
# of resources that should depend on this resource agent are Filesystem resource
# agent that mount OCFS2 volumes that reside on EVMS2 volumes in a shared 
# EVMS2 cluster container.
#
# For this resource agent to do it's job correctly, evmsd must be running on
# the node where the agent is started. Usually evmsd is started by the cluster
# software via a respawn statement in /etc/ha.d/ha.cf. If you encounter timing
# issues where evmsd is not yet started but where the cluster already starts
# the EvmsSCC clone, then you should comment out the evmsd respawn statement
# in /etc/ha.d/ha.cf and start evmsd on each node in the cluster via a separate
# clone resource agent. The EvmsSCC resource agent cloneset should then be made
# dependent to this evmsd cloneset. This will guarantee that emvsd is running
# before EvmsSCC is started, on each node in the cluster.
#

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

. ${OCF_ROOT}/resource.d/heartbeat/.ocf-shellfuncs

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


# Utilities used by this script
CUT=cut
EVMSACTIVATE=evms_activate

usage() {
	cat <<-EOT
	usage: $0 {start|stop|status|monitor|meta-data}
	EOT
}

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

<longdesc lang="en">
Resource script for EVMS shared cluster container. It runs evms_activate on one node in the cluster.
</longdesc>
<shortdesc lang="en">EVMS SCC resource agent</shortdesc>

<actions>
<action name="start" timeout="60" />
<action name="stop" timeout="60" />
<action name="notify" timeout="60" />
<action name="status" depth="0" timeout="10" interval="10" start-delay="10" />
<action name="monitor" depth="0" timeout="10" interval="10" start-delay="10" />
<action name="meta-data" timeout="5" />
</actions>
</resource-agent>
END
}

EvmsSCC_status()
{
	# At the moment we don't support monitoring EVMS activations. We just return "not running" to cope with the pre-start monitor call.
	return $OCF_NOT_RUNNING
}

EvmsSCC_notify()
{
	local n_type="$OCF_RESKEY_CRM_meta_notify_type"
        local n_op="$OCF_RESKEY_CRM_meta_notify_operation"
        local n_active="$OCF_RESKEY_CRM_meta_notify_active_uname"
        local n_stop="$OCF_RESKEY_CRM_meta_notify_stop_uname"
        local n_start="$OCF_RESKEY_CRM_meta_notify_start_uname"

	case "$n_type" in
        pre)
                case "$n_op" in
                start)  ocf_log debug "EvmsSCC: Notify: Starting node(s): $n_start."
			EvmsSCC_start_notify_common
                        ;;
                esac
                ;;
	esac
	

	return $OCF_SUCCESS
}

EvmsSCC_start()
{   
	local n_type="$OCF_RESKEY_CRM_meta_notify_type"
	local n_op="$OCF_RESKEY_CRM_meta_notify_operation"
	local n_active="$OCF_RESKEY_CRM_meta_notify_active_uname"
	local n_stop="$OCF_RESKEY_CRM_meta_notify_stop_uname"
	local n_start="$OCF_RESKEY_CRM_meta_notify_start_uname"

        ocf_log debug "EvmsSCC: Start: starting node(s): $n_start."
	
	EvmsSCC_start_notify_common

	return $OCF_SUCCESS
}

EvmsSCC_stop()
{
	return $OCF_SUCCESS
}

EvmsSCC_start_notify_common()
{
	local n_myself=${HA_CURHOST:-$(uname -n | tr A-Z a-z)}
        ocf_log debug "EvmsSCC: Start_Notify: I am node $n_myself."

        n_active="$n_active $n_start"
        case " $n_active " in
        *" $n_myself "*) ;;
        *)      ocf_log err "EvmsSCC: $n_myself (local) not on active list!"
                return $OCF_ERR_GENERIC
                ;;
        esac

	#pick the first node from the starting list
	#when the cluster boots this will be one of the many booting nodes 
	#when a node later joins the cluster, this will be the joining node 
        local n_first=$(echo $n_start | cut -d ' ' -f 1)
        ocf_log debug "EvmsSCC: Start_Notify: First node in starting list is $n_first."

        if [ "$n_myself" = "$n_first" ] ; then
                ocf_log debug "EvmsSCC: Start_Notify: I am running evms_activate."
                EVMS_OUTPUT="startvalue"
                while [ -n "$EVMS_OUTPUT" ] ; do
                        EVMS_OUTPUT=`evms_activate 2>&1`
                        if [ -n "$EVMS_OUTPUT" ] ; then
                                SLEEP_TIME=$(($RANDOM % 40))
                                ocf_log info "EvmsSCC: Evms call failed - sleeping for $SLEEP_TIME seconds and then trying again."
                                sleep $SLEEP_TIME
                        else
                                break
                        fi
                done

        fi

        return $OCF_SUCCESS
}

# Check the arguments passed to this script
if
  [ $# -ne 1 ]
then
  usage
  exit $OCF_ERR_ARGS
fi

OP=$1

case $OP in
  meta-data)		meta_data
			exit $OCF_SUCCESS
			;;
  usage)		usage
			exit $OCF_SUCCESS
			;;
esac

check_binary $CUT
check_binary $EVMSACTIVATE

case $OP in
  start)	        EvmsSCC_start
			;;
  notify)		EvmsSCC_notify	
			;;
  stop)			EvmsSCC_stop	
			;;
  status|monitor)	EvmsSCC_status
			;;
  *)			usage
			exit $OCF_ERR_UNIMPLEMENTED
			;;
esac
exit $?
