#!/bin/sh

# Copyright (C) 2009  Citrix Systems Inc.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

LANG="C"
export LANG

usage() {
    echo "$0 [ -p <pidfile> ]" >&2
    exit 1
}

# Parse command line opts
while [ $# -ne 0 ] ; do
    arg="$1"
    shift
    case "$arg" in
        "-p")
            [ $# -eq 0 ] && usage
            pidfile="$1"
            shift
            mkdir -p "$(dirname "$pidfile")"
            echo $$ > "$pidfile"
            ;;
        *)
            usage
            ;;
    esac
done

XE_UPDATE_GUEST_ATTRS=/usr/local/sbin/xe-update-guest-attrs
XE_DAEMON_RATE=60           # run once a minute by default
XE_MEMORY_UPDATE_DIVISOR=2  # update mem stats 1/2 as often by dflt

# Delete xenstore cache following each reboot
rm -rf /var/cache/xenstore

# seed the xe-linux-distribution cache file for Xen
cat > /var/cache/xe-linux-distribution <<FOO
os_distro="`uname -s`"
os_majorver=""
os_minorver=""
os_uname="`uname -r`"
os_name="`uname -s` `uname -r`"
FOO

MEMORY_UPDATE_COUNTER=0
while true ; do 
    if [ ${MEMORY_UPDATE_COUNTER} -eq 0 ] ; then
	MEMORY=--memory
	MEMORY_UPDATE_COUNTER=${XE_MEMORY_UPDATE_DIVISOR}
    else
	MEMORY=
    fi
    MEMORY_UPDATE_COUNTER=$((${MEMORY_UPDATE_COUNTER} - 1))
    ${XE_UPDATE_GUEST_ATTRS} ${MEMORY}

    sleep ${XE_DAEMON_RATE}
done
