#!/usr/bin/ksh
#
# zone_console - simple script to start and stop zone console session in screen sessions
#
# History
#   05.09.2009/bs 
#       initial release
#
# reuqirements
#   screen must be installed
#   screen homepage: http://www.gnu.org/software/screen/
#
# CDDL HEADER START
#
# The contents of this file and the script are subject to the terms of the
# Common Development and Distribution License, Version 1.0 only
# (the "License").  You may not use this file except in compliance
# with the License.
#
# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
# or http://www.opensolaris.org/os/licensing.
# See the License for the specific language governing permissions
# and limitations under the License.
#
# When distributing Covered Code, include this CDDL HEADER in each
# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
# If applicable, add the following below this CDDL HEADER, with the
# fields enclosed by brackets "[]" replaced with your own identifying
# information: Portions Copyright [yyyy] [name of copyright owner]
#
# CDDL HEADER END

# this script
#
_THIS_SCRIPT="${0##*/}"

# additional options for the screen sessions
#
ADD_START_SCREEEN_OPTIONS=""

ADD_CONNECT_SCREEN_OPTIONS=""

# get the list of installed zones
#
LIST_OF_ZONES="$( zoneadm list -i | grep -v global )"

# sub routines

logMsg() {
  echo "[${_THIS_SCRIPT}] $*"
}


logInfo() {
  [ "${VERBOSE}"X != ""X ] && logMsg "INFO: $*"
}

logError() {
  logMsg "ERROR: $*" >&2
}

die () {
  typeset THISRC=$1
  if [ $# -ne 0 ] ; then
    shift
    typeset THISMSG="$*"
    [ "${THISRC}"x = "0"x ] && logMsg "${THISMSG}" ||  logError "${THISMSG}" 
  fi
  exit  ${THISRC}
}

zone_exist() {
 [ $# -eq 1 ] &&  zoneadm -z $1 list  2>/dev/null >/dev/null || return 1
}

screen_session_running() {
 [ $# -eq 1 ] && screen -list  | cut -f2 | grep "^[0-9]*\." | cut -f2 -d "." | grep "${1}_console" >/dev/null || return 1
}

get_screen_pid() {
  [ $# -eq 1 ] && screen -list  | cut -f2 | grep  "^[0-9]*\." | grep "${1}_console" | cut -f1  -d "."  || return 1
}

start_screen_session() {
  typeset CUR_ZONE="$1"
  [ $# -eq 1 ] && screen -dmS "${CUR_ZONE}_console" ${ADD_START_SCREEEN_OPTIONS} zlogin -C ${CUR_ZONE}
}

connect_screen_session() {
  typeset CUR_ZONE="$1"
  [ $# -eq 1 ] && screen -S "${CUR_ZONE}_console" -R -DD  ${ADD_CONNECT_SCREEEN_OPTIONS}
}


# --- main function ---

# check the prerequisites
#
[ "$( id | sed 's/uid=\([0-9]*\)(.*/\1/' )" = 0 ] || die 100 "This script must be executed by root"

for CUR_BINARY in screen zoneadm zlogin ; do
  whence "${CUR_BINARY}" 2>/dev/null >/dev/null || die 101 "\"${CUR_BINARY}\" is NOT installed or NOT available via the path variable"
done

# execute the requested function
#

case $1 in

  start )
    shift
    [ $# -ne 0 ] && LIST_OF_ZONES="$*"
    logInfo "Starting the screen sessions for the console of the zones ${LIST_OF_ZONES}\" ..."
   
    for CUR_ZONE in ${LIST_OF_ZONES} ; do
      zone_exist "${CUR_ZONE}" 
      if [ $? -ne 0 ] ; then
        logError "Zone \"${CUR_ZONE}\" does NOT exist"    
        continue
      fi

      if screen_session_running "${CUR_ZONE}" ; then
        logMsg "Screen session for the console of the the zone \"${CUR_ZONE}\" is already running"
      else
        logMsg "Starting the screen session for the console of the zone \"${CUR_ZONE}\" ..."
        start_screen_session "${CUR_ZONE}"
      fi
    done
    ;;
    
  stop )
    shift
    [ $# -ne 0 ] && LIST_OF_ZONES="$*"
    logInfo "Stoping the screen sessions for the console of the zones \"${LIST_OF_ZONES}\" ..."
  
    for CUR_ZONE in ${LIST_OF_ZONES} ; do
      zone_exist "${CUR_ZONE}" 
      if [ $? -ne 0 ] ; then
        logError "The zone \"${CUR_ZONE}\" does NOT exist"    
        continue
      fi
    
      if screen_session_running "${CUR_ZONE}" ; then
        logMsg "Stoping the screen session for the console of the zone \"${CUR_ZONE}\" ..."
        SCREEN_PID="$( get_screen_pid ${CUR_ZONE} )"
        [ "${SCREEN_PID}"X != ""X ] && kill ${SCREEN_PID} || logMsg "Warning: Can NOT detect the PID of this screen session"
      else
        logMsg "The screen session for the console of the zone \"${CUR_ZONE}\" is NOT running"
      fi
    done
    ;;


  status )  
    shift
    [ $# -ne 0 ] && LIST_OF_ZONES="$*"
    logInfo "Checking the status of the screen session for the console of the zones \"${LIST_OF_ZONES}\" ..."
  
    for CUR_ZONE in ${LIST_OF_ZONES} ; do
      zone_exist "${CUR_ZONE}" 
      if [ $? -ne 0 ] ; then
        logError "The zone \"${CUR_ZONE}\" does NOT exist"    
        continue
      fi
    
      if screen_session_running "${CUR_ZONE}" ; then
        logMsg "The screen session for the console of the zone \"${CUR_ZONE}\" is running"
      else
        logMsg "The screen session for the console of the zone \"${CUR_ZONE}\" is NOT running"
      fi
    done
    ;;

  "-h" | "--help" | "-?" )
    logMsg "Usage: $0 [start {zone1 ... zone#}|stop {zone1 ... zone#}|status {zone1 ...zone#}|{console} zone]"
    exit 5
    ;;
    
  * )
    [ "$1"x = "console"x ] && shift

    [ $# -eq 1 ] || die 10 "Invalid usage"
 
    CUR_ZONE="$1"
    zone_exist "${CUR_ZONE}" || die 15 "The zone \"${CUR_ZONE}\" does NOT exist"
    screen_session_running "${CUR_ZONE}" 
    if [ $? -ne 0 ] ; then
      logMsg "Starting the screen session for the console of the zone \"${CUR_ZONE}\" ..."
      start_screen_session "${CUR_ZONE}"
    fi

    logInfo "The console for the zone \"${CUR_ZONE}\" is already running, now connecting ..."
    connect_screen_session "${CUR_ZONE}"
    ;;
  
esac