#!/bin/sh
#
# Bareos interface to mtx autoloader
#
#  If you set in your Device resource
#
#  Changer Command = "path-to-this-script/mtx-changer %c %o %S %a %d"
#    you will have the following input to this script:
#
#  So Bareos will always call with all the following arguments, even though
#    in come cases, not all are used.
#
#  mtx-changer "changer-device" "command" "slot" "archive-device" "drive-index"
#		   $1		   $2	    $3	      $4	       $5
#
#  for example:
#
#  mtx-changer /dev/sg0 load 1 /dev/nst0 0 (on a Linux system)
#
#  will request to load the first cartidge into drive 0, where
#   the SCSI control channel is /dev/sg0, and the read/write device
#   is /dev/nst0.
#
#  The commands are:
#      Command		  Function
#      unload		  unload a given slot
#      load		  load a given slot
#      loaded		  which slot is loaded?
#      list		  list Volume names (requires barcode reader)
#      slots		  how many slots total?
#      listall		  list all info
#      transfer
#
#  Slots are numbered from 1 ...
#  Drives are numbered from 0 ...
#
#
#  If you need to an offline, refer to the drive as $4
#    e.g.   mt -f $4 offline
#
#  Many changers need an offline after the unload. Also many
#   changers need a sleep 60 after the mtx load.
#
#  N.B. If you change the script, take care to return either
#   the mtx exit code or a 0. If the script exits with a non-zero
#   exit code, Bareos will assume the request failed.
#
# How long we should wait the drive
# can be overriden in configuration file
max_wait_drive=300

# source our conf file
if test ! -r "${BAREOS_CONFIG_DIR:-@confdir@}/mtx-changer.conf"; then
  echo "!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"
  echo "ERROR: ${BAREOS_CONFIG_DIR:-@confdir@}/mtx-changer.conf file not found!!!!"
  echo "!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"
  exit 1
fi
. "${BAREOS_CONFIG_DIR:-@confdir@}/mtx-changer.conf"

MTX=${MTX:-@MTX@}
if test ! -x "${MTX}"; then
  echo "ERROR: mtx program not found (${MTX})"
  exit 1
fi

dbgfile="${logdir:-@logdir@}/mtx.log"
if test ${debug_log} -ne 0; then
  touch "${dbgfile}"
fi
debug()
{
  if test -f "${dbgfile}"; then
    echo "$(date +"%Y%m%d-%H:%M:%S") $*" >>"${dbgfile}"
  fi
}

#
# Create a temporary file
#
make_temp_file()
{
  TMPFILE=$(mktemp "${working_dir:-@working_dir@}/mtx.XXXXXXXXXX")
  if test "x${TMPFILE}" = "x"; then
    TMPFILE="${working_dir:-@working_dir@}/mtx.$$"
    if test -f "${TMPFILE}"; then
      echo "ERROR: Temp file security problem on: ${TMPFILE}"
      exit 1
    fi
  fi
}

#
#  Create a temporary file for stderr
#
#  Note, this file is used because sometime mtx emits
#  unexpected error messages followed by the output
#  expected during success.
#  So we separate STDOUT and STDERR in
#  certain of the mtx commands. The contents of STDERR
#  is then printed after the STDOUT produced by mtx
#  thus we sometimes get better changer results.
#
make_err_file()
{
  ERRFILE=$(mktemp ${working_dir:-@working_dir@}/mtx.err.XXXXXXXXXX)
  if test "x${ERRFILE}" = "x"; then
    ERRFILE="${working_dir:-@working_dir@}/mtx.err.$$"
    if test -f "${ERRFILE}"; then
      echo "ERROR: Temp file security problem on: ${ERRFILE}"
      exit 1
    fi
  fi
}

#
# The purpose of this function to wait a maximum
#   time for the drive. It will
#   return as soon as the drive is ready, or after
#   waiting a maximum of 300 seconds.
# Note, this is very system dependent, so if you are
#   not running on Linux, you will probably need to
#   re-write it, or at least change the grep target.
#   We've attempted to get the appropriate OS grep targets
#   in the code at the top of this script.
#
wait_for_drive()
{
  i=0
  while [ ${i} -le ${max_wait_drive} ]; do
    debug "Doing mt -f $1 status ..."
    drivestatus=$(mt -f "$1" status 2>&1)
    if echo "${drivestatus}" | grep "${ready}" >/dev/null 2>&1; then
      break
    fi
    debug "${drivestatus}"
    debug "Device $1 - not ready, retrying ..."
    sleep 1
    i=$(expr ${i} + 1)
  done
}

# check parameter count on commandline
#
check_parm_count()
{
  pCount=$1
  pCountNeed=$2
  if test ${pCount} -lt ${pCountNeed}; then
    echo "ERROR: usage: mtx-changer ctl-device command [slot archive-device drive-index]"
    echo "	Insufficient number of arguments given."
    if test ${pCount} -lt 2; then
      echo "  Mimimum usage is first two arguments ..."
    else
      echo "  Command expected ${pCountNeed} arguments"
    fi
    exit 1
  fi
}

# Check for special cases where only 2 arguments are needed,
#  all others are a minimum of 5
#
case $2 in
  list | listall)
    check_parm_count $# 2
    ;;
  slots)
    check_parm_count $# 2
    ;;
  transfer)
    check_parm_count $# 4
    ;;
  *)
    check_parm_count $# 5
    ;;
esac

# Setup arguments
ctl=$1
cmd="$2"
slot=$3
device=$4
drive=$5

debug "Parms: ${ctl} ${cmd} ${slot} ${device} ${drive}"

case "${cmd}" in
  unload)
    debug "Doing mtx -f ${ctl} unload ${slot} ${drive}"

    if test ${offline} -eq 1; then
      mt -f "${device}" offline
    fi
    if test ${offline_sleep} -ne 0; then
      sleep ${offline_sleep}
    fi
    make_err_file
    ${MTX} -f "${ctl}" unload ${slot} ${drive} 2>"${ERRFILE}"
    rtn=$?
    cat "${ERRFILE}"
    rm -f "${ERRFILE}" >/dev/null 2>&1
    exit $rtn
    ;;

  load)
    debug "Doing mtx -f ${ctl} load ${slot} ${drive}"
    make_err_file
    ${MTX} -f "${ctl}" load ${slot} ${drive} 2>"${ERRFILE}"
    rtn=$?
    if test ${load_sleep} -ne 0; then
      sleep ${load_sleep}
    fi
    wait_for_drive ${device}
    cat "${ERRFILE}"
    rm -f "${ERRFILE}" >/dev/null 2>&1
    exit $rtn
    ;;

  list)
    debug "Doing mtx -f ${ctl} -- to list volumes"
    make_temp_file
    if test ${inventory} -ne 0; then
      ${MTX} -f "${ctl}" inventory
    fi
    ${MTX} -f "${ctl}" status >"${TMPFILE}"
    rtn=$?
    #if test ${vxa_packetloader} -ne 0 ; then
    #  cat "${TMPFILE}" | grep " *Storage Element [0-9]*:.*Full" | sed "s/ Storage Element //" | sed "s/Full :VolumeTag=//"
    #else
    #  cat "${TMPFILE}" | grep " Storage Element [0-9]*:.*Full" | awk "{print \$3 \$4}" | sed "s/Full *\(:VolumeTag=\)*//"
    #fi
    # We shouldn't have a difference with this pattern
    awk -F ":" -f - "${TMPFILE}" <<'_EOT_'
    /^ .*Storage Element .*[0-9]:.*Full/ {
      gsub("[ ].*Storage Element ","",$1)
      gsub("VolumeTag=","",$3)
      gsub(/ *$/, "", $3)
      print $1 ":" $3
    }
_EOT_

    awk -f - "$TMPFILE" <<'_EOT_'
    /^Data Transfer Element [0-9]*:Full \(Storage Element [0-9]/ {
      printf "%s:%s\n",$7,$10
    }
_EOT_
    rm -f "${TMPFILE}" >/dev/null 2>&1
    exit $rtn
    ;;

  listall)
    #  Drive content:	  D:Drive num:F:Slot loaded:Volume Name
    #  D:0:F:2:vol2        or D:Drive num:E
    #  D:1:F:42:vol42
    #  D:3:E
    #
    #  Slot content:
    #  S:1:F:vol1		  S:Slot num:F:Volume Name
    #  S:2:E	       or S:Slot num:E
    #  S:3:F:vol4
    #
    #  Import/Export tray slots:
    #  I:10:F:vol10 	  I:Slot num:F:Volume Name
    #  I:11:E	       or I:Slot num:E
    #  I:12:F:vol40

    debug "Doing mtx -f $ctl -- to list all"
    make_temp_file
    if test ${inventory} -ne 0; then
      ${MTX} -f "${ctl}" inventory
    fi
    ${MTX} -f "${ctl}" status >"${TMPFILE}"
    rtn=$?
    awk -F ":" -f - "${TMPFILE}" <<'_EOT_'
    /^Data Transfer Element .*[0-9]:/ {
      gsub("Data Transfer Element ","",$1)
      match($2,/Full \(Storage Element ([0-9]{1,}) Loaded\)/)
      if (RSTART > 0 ) {
        T=substr($2,RSTART,RLENGTH)
        match(T,/[0-9]{1,}/)
        F=":F:" substr(T,RSTART,RLENGTH)
      }
      else {
        F=$2
      }
      gsub("Empty",":E",F)
      gsub("VolumeTag = ",":",$3)
      print "D:" $1 F $3
    }
_EOT_
    awk -F ":" -f - "${TMPFILE}" <<'_EOT_'
    /^ .*Storage Element .*[0-9]:/ {
      gsub("[ ].*Storage Element ","",$1)
      gsub("Full ",":F",$2)
      gsub("Empty",":E",$2)
      gsub("VolumeTag=",":",$3)
      print "S:" $1  $2  $3
    }
_EOT_
    awk -F ":" -f - "${TMPFILE}" <<'_EOT_'
    /^ .*Storage Element .*[0-9] IMPORT\/EXPORT:/ {
      gsub("[ ].*Storage Element ","",$1)
      gsub(" IMPORT/EXPORT","",$1)
      gsub("Full ",":F",$2)
      gsub("Empty",":E",$2)
      gsub("VolumeTag=",":",$3)
      print "I:"$1 $2 $3
    }
_EOT_
    rm -f "${TMPFILE}" >/dev/null 2>&1
    exit $rtn
    ;;

  transfer)
    slotdest=$device
    debug "Doing transfer from ${slot} to ${slotdest}"
    ${MTX} -f "${ctl}" transfer ${slot} ${slotdest}
    rtn=$?
    exit $rtn
    ;;

  loaded)
    debug "Doing mtx -f $ctl ${drive} -- to find what is loaded"
    make_temp_file
    ${MTX} -f "${ctl}" status >"${TMPFILE}"
    rtn=$?
    awk "/^Data Transfer Element ""${drive}"":Full/ {print \$7}" "$TMPFILE"
    awk "/^Data Transfer Element ""${drive}"":Empty/ {print 0}" "$TMPFILE"
    rm -f "${TMPFILE}" >/dev/null 2>&1
    exit $rtn
    ;;

  slots)
    debug "Doing mtx -f ${ctl} -- to get count of slots"
    ${MTX} -f "${ctl}" status | awk "/^  Storage Changer .*:/ {print \$5}"
    ;;
esac
