#!/bin/bash

# Distributed under the terms of the GNU General Public License v2
#
# Copyright 2001-2010 LINBIT Information Technologies
# Philipp Reisner, Lars Ellenberg
#
# Copyright 2010-2011 Source Mage Team
# Vlad Glagolev

PROGRAM=/bin/false
RUNLEVEL=3
NEEDS="+local_fs +network"

. /etc/init.d/smgl_init

DRBDADM="/sbin/drbdadm"
DRBDSETUP="/sbin/drbdsetup"
PROC_DRBD="/proc/drbd"
MODPROBE="/sbin/modprobe"
RMMOD="/sbin/rmmod"
UDEV_TIMEOUT=10
ADD_MOD_PARAM=""

function assure_module_is_loaded {
  [ -e "$PROC_DRBD" ] && return
  echo "Loading drbd module..."

  $MODPROBE -s drbd `$DRBDADM sh-mod-parms` $ADD_MOD_PARAM || return 1

  return 0
}

function adjust_with_progress {
  local IFS_O=$IFS
  local IFS=$'\n'
  local res out

  COMMANDS=`$DRBDADM -d -n res adjust all` || return 1

  echo -n "[ "

  for CMD in $COMMANDS; do
    IFS=$IFS_O

    case "$CMD" in
      res=*)
        eval "$CMD"
      ;;
      *\ disk\ *)
        # Check for offline resize. If using internal meta data,
        # we may need to move it first to its expected location.
        out=$($DRBDADM check-resize "$res" 2>&1)
        [[ -z $out ]] ||
        printf "\n%s\n%s\n" "$res" "$out"
        echo -n "d($res) "
      ;;
      *\ syncer\ *)
        echo -n "s($res) "
      ;;
      *\ net\ *)
        echo -n "n($res) "
      ;;
      *)
        echo ".. "
      ;;
    esac

    if ! eval "$CMD"; then
       printf "[%s] cmd %s failed - continuing!\n" "$res" "$CMD"
    fi
  done

  echo -n "]"

  return 0
}

start() {
  # Just in case drbdadm want to display any errors in the configuration
  # file, or we need to ask the user about registering this installation
  # at http://usage.drbd.org, we call drbdadm here without any IO
  # redirection.
  $DRBDADM sh-nop

  assure_module_is_loaded
  evaluate_retval

  echo "Starting DRBD resources:"

  adjust_with_progress
  evaluate_retval

  # make sure udev has time to create the device files
  echo "Waiting for udev device creation..."

  for RESOURCE in `$DRBDADM sh-resources`; do
    for DEVICE in `$DRBDADM sh-dev $RESOURCE`; do
      UDEV_TIMEOUT_LOCAL=$UDEV_TIMEOUT
      while [[ ! -e $DEVICE ]] && [[ $UDEV_TIMEOUT_LOCAL -gt 0 ]]; do
        sleep 1
        UDEV_TIMEOUT_LOCAL=$(( $UDEV_TIMEOUT_LOCAL-1 ))
      done
    done
  done

  echo "Waiting for connection "
  $DRBDADM wait-con-int # User interruptible version of wait-connect all
  $DRBDADM sh-b-pri all # Become primary if configured

  evaluate_retval
}

stop() {
  $DRBDADM sh-nop
  echo "Stopping all DRBD resources..."

  if [ -e $PROC_DRBD ]; then
    # bypass drbdadm and drbd config file and everything,
    # to avoid leaving devices around that are not referenced by
    # the current config file, or in case the current config file
    # does not parse for some reason.
    for d in /dev/drbd* ; do
      [ -L "$d" ] && continue
      [ -b "$d" ] || continue

      M=$(umount "$d" 2>&1)

      case $M in
        *" not mounted")
          :
        ;;
        *)
          echo "$M" >&2
        ;;
      esac

      $DRBDSETUP "$d" down
    done

    $RMMOD drbd
  fi

  evaluate_retval
}

status() {
  if [ -e $PROC_DRBD ]; then
    echo "device status:"
    cat $PROC_DRBD
  else
    echo "drbd module not loaded"
    return 1
  fi
}

restart() {
  echo "Restarting all DRBD resources..."

  stop
  sleep 1
  start
}

reload() {
  $DRBDADM sh-nop
  echo "Reloading DRBD configuration..."
  $DRBDADM adjust all

  evaluate_retval
}