#! /bin/sh
#
# Author      : Carsten Grohmann
#
# Date        : 08. December 2003
#
  VERSION="0.4";
#
# Licence     : GPL
#
# State       : runs fine
#
# Syntax      : none
#
# Execute amdump and amverify with multiple optionsmultiple like
#   - no dumps on holydays and other free days
#   - save the mysql database before the dump
#   - only one crontab entry instead of several entries
#   - you can labeling monthly tapes automatically and mark them as no-reuse
#
# return values:
#  - 10  user is not AMANDA_USER
#  - 20  no tape in device
#  - 30  error during labeling the tape
#

# BEGIN USER CONFIG
###################

# Weekdays to force a full backup
# More entries are seperated by a space character
# It is also possible to use a range of weekdays. In this case you can use
# firstweekday-lastweekday.
# Format of the entries: 
# Sunday = 0, Monday = 1, ...
# Example: "5-6 0" means no backup Friday, Saturday and Sunday
WEEKDAY_FORCE_FULL_DUMP="5"

# Parts of the backup to force a full backup on level 0
# More entries are seperated by a space character.
# Format of the entries:
#   computer_name:/directory
#   more entries are seperated by a space character
# Example: "localhost:/home/exampleuser" oder "mycomputer:/home/only_me"
FORCE_FULL_DUMP="localhost:/example my.domain.tld:/home"

# Amanda configuration
BACKUP_CONFIG="example"

# Days without backup like holydays.
# More entries are seperated by a space character.
# It is also possible to use a range of days. In this case you can use
# firstday-lastday.
# Format of the entries: YYYYMMDD
# Example: 20031224 means no backup on Chrismas Eve
NOBACKUP_DAYS="20030102 20030103 20030418-20030421 \
               20030501 20030502 20030529 20030609 \
	       20031003 20031119 20031223-20040102"
	       
# Days on with the tape should be labled
# More entries are seperated by a space character.
# Format of the entries: YYYYMMDD:NewLabel
# Example: 20031219:Dezember2003 labled the tape on 19.12.2003 with the 
#          name Dezember2003
LABEL_DAYS="20031219:Dezember2003"

# mark the via LABEL_DAYS labeled types as no-reuse
MARK_NOREUSE="yes"
		
# Weekdays without backup.
# More values are seperated by a space character.
# You could use this option instead day based cronjobs
NOBACKUP_WEEKDAYS=""

# userid of the amanda programs
AMANDA_USER="amanda"

# runs amverify to verify your backup
# default: should be "yes"
USE_AMVERIFY="yes"

# run $MYSQLBACKUP to save the databases
USE_MYSQLBACKUP="yes"

# print messages
VERBOSE="no"

# END USER CONFIG
#################

# program settings -- do NOT change

TIME=$(date '+%d.%m.%Y %H:%M')
TODAY=$(date '+%Y%m%d')
WEEKDAY=$(date '+%w')

SCRIPT_USER=$(id -un)
DEVICE="/dev/nst0"

# program files
AMDUMP="/usr/sbin/amdump"
AMVERIFY="/usr/sbin/amverify"
AMADMIN="/usr/sbin/amadmin"
AMLABEL="/usr/sbin/amlabel"
MYSQLBACKUP="/usr/bin/mysql_backup.pl"

# Own functions
###############

# Show the info message
function do_info () {
test $VERBOSE = yes && echo -e $*
}

# Show a waring message
function do_warning () {
  echo "WARNING:" $*
}

# Show a error message
function do_error () {
  echo "ERROR:" $*
}

# finish the script
function do_exit () {
  do_info "Script finished"
  exit $1
}


function is_range () {
  echo $1 | grep --silent "-"
}

# 1. first day
# 2. today
# 3. last day
function is_inrange() {
# only to better human read
  my_firstday=$1
  my_today=$2
  my_lastday=$3
  test $my_firstday -le $my_today -a $my_today -le $my_lastday
}


# Program
#########

# print program name and version
do_info "`basename $0` Version $VERSION"

trap do_exit SIGHUP SIGSTOP SIGKILL SIGTERM

# check userid
if [ "$SCRIPT_USER" != "$AMANDA_USER" ]; then
  do_error "You are not user $AMANDA_USER. Please start this script as user $AMANDA_USER or change the settings."
  do_exit 10
fi  

# check days without backup
for i in $NOBACKUP_DAYS; do
  if is_range "$i"; then
    FIRSTDAY=${i%-*}
    LASTDAY=${i#*-}
    if is_inrange $FIRSTDAY $TODAY $LASTDAY; then
      do_info "No backup today ($TODAY)"
      do_exit
    fi
  elif [ "$i" -eq "$TODAY" ]; then
    do_info "No backup today ($TODAY)"    
    do_exit
  fi  
done  

# check weekday without backup
for i in $NOBACKUP_WEEKDAYS; do
  if is_range "$i"; then
    FIRSTDAY=${i%-*}
    LASTDAY=${i#*-}
    if is_inrange $FIRSTDAY $WEEKDAY $LASTDAY; then
      do_info "No backup this weekday ($WEEKDAY)"
      do_exit
    fi
  elif [ "$i" -eq "$WEEKDAY" ]; then
    do_info "No backup this weekday ($WEEKDAY)"
    do_exit
  fi
done

# check tape
mt -f $DEVICE status >/dev/null 2>&1
if [ $? != 0 ]; then
  do_error "No tape in device $DEVICE. The backup failed."
  do_exit 20
fi

# check day to label tape
for i in $LABEL_DAYS; do
  LDAY=${i%:*}
  LLABEL=${i#*:}
  if [ "$TODAY" = "$LDAY" ]; then
    $AMLABEL $BACKUP_CONFIG $LLABEL
    if [ "$?" != "0" ]; then
      do_error "During label the tape"
      do_exit 30
    fi
    if [ "$MARK_NOREUSE" = "yes" ]; then
      NO_REUSE=$LLABEL
    fi
  fi
  unset LDAY;
  unset LLABEL;
done

# force full backup
for i in $WEEKDAY_FORCE_FULL_DUMP; do
  if [ "$i" -eq "$WEEKDAY" ]; then
    for j in $FORCE_FULL_DUMP; do
      do_info "force full dump for for ${j//:/ }"
      $AMADMIN $BACKUP_CONFIG force ${j//:/ }
    done
  fi
done

# dump MySQL database
if [ "$USE_MYSQLBACKUP" = "yes" ]; then
  do_info "Save MySQL databases:"
  $MYSQLBACKUP >/dev/null 2>&1
  if [ $? -ne 0 ]; then
    do_error "Backup of the MySQL databases failed"
  fi
fi  

# write backup: call Amanda amdump
do_info "Amdump started:"
$AMDUMP $BACKUP_CONFIG >/dev/null 2>&1

# verify backup: call Amanda amverify
if [ "$USE_AMVERIFY" = "yes" ]; then
  do_info "Amverify started:"
  $AMVERIFY $BACKUP_CONFIG >/dev/null 2>&1
fi

# mark monthly tapes as no reuseable
if [ "$NO_REUSE" ]; then
  do_info "Mark $NO_REUSE as no-reuse"
  $AMADMIN $BACKUP_CONFIG no-reuse $NO_REUSE >/dev/null 2>&1
fi

do_info "Backup finished"
do_exit