#! /bin/sh
# This file is part of BEAM
# Copyright (C) 2012-2014 Sergey Poznyakoff
#
# BEAM 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 3, or (at your option)
# any later version.
#
# BEAM 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 BEAM.  If not, see <http://www.gnu.org/licenses/>.

# Force C locale
LC_ALL=C
export LC_ALL

openlog_hook=
prologue_hook=
epilogue_hook=

# User configuration variables
backup_tar_options=
backup_suffix=
backup_archive_dir=
backup_snapshot_dir=
backup_verbose=
backup_logfile="/var/log/backup"
backup_pidfile="/var/run/beam.pid"
backup_tmp_dir=/tmp

error() {
    echo >&2 $0: $*
}

logit() {
    echo `date`: $*
}

abend() {
    ec=$1
    shift
    error $@
    exit $ec
}

beam_lock() {
    if [ -r $backup_pidfile ]; then
	pid=$(head -n 1 $backup_pidfile)
	if [ -z "$pid" ]; then
	    abend 1 "pidfile $backup_pidfile exists but is unreadable or empty"
	fi
	abend 1 "another beam process (pid $pid) is still running; exiting"
    fi
    echo $$ > $backup_pidfile || exit 1
    epilogue_hook="$epilogue_hook beam_unlock"
}  

beam_unlock() {
    rm -f $backup_pidfile
}  

tarcode() {
    case $1 in
    0) logit "success";;
    1) logit "some files changed while being archived";;
    2) logit "fatal error occurred, but trying to continue anyway"
       tarerror=$((tarerror + 1));;
    *) logit "unexpected error code $1"
       tarerror=$((tarerror + 1));
    esac
}

load_config() {
    local delayed_exit remote 
  
    test -z "$BEAM_CONFIG" && BEAM_CONFIG=@SYSCONFDIR@/beam.conf
    if [ -r $BEAM_CONFIG ]; then
	. $BEAM_CONFIG
    else
        abend 1 "configuration file $BEAM_CONFIG does not exist or is unreadable"
    fi
  
    if [ -z "$backup_items" ]; then
        abend 1 "backup_items not specified"
    fi

    if [ -z "$backup_archive_dir" ]; then
        if [ -n "$backup_bucket_name" ]; then
            backup_archive_dir=$backup_mp_s3
        else
            abend 1 "backup_archive_dir not set"
        fi
    fi

    delayed_exit=
    loaded_types=
    for item in $backup_items
    do
	eval type=\$${item}_type
        if [ -z "$type" ]; then
	    error "${item}_type not set"
	    delayed_exit=1
	    continue
	fi
  
	if echo "$loaded_types" | grep -wq $type; then
	    :
	elif [ -x $libdir/${type}.sh ]; then
	    . $libdir/${type}.sh || delayed_exit=1
	    loaded_types="$loaded_files
$type"
	else
	    error "$libdir/${type}.sh not found"
	    delayed_exit=1 
	fi

	${type}_check $item || delayed_exit=1
    done

    test -n "$delayed_exit" && abend 1 "aborting"

    tar_suffix=${backup_suffix:-.tar}

    if [ -n "$backup_bucket_name" ]; then
	. @LIBDIR@/beam/s3.sh
	prologue_hook="s3_mount $prologue_hook"
    fi

    remote=${backup_archive_dir%%:*}
    if [ "$remote" != "$backup_archive_dir" ]; then
	beam_rsh="${backup_rsh:-ssh} $remote"
	backup_local_archive_dir=${backup_archive_dir#*:}
    else
	beam_rsh=
	backup_local_archive_dir=$backup_archive_dir
    fi
}

beam_exec() {
    if [ -z "$beam_rsh" ]; then
	set -- $(echo "$@" | sed 's/\\\\\([bcfnrtv0]\)/\\\1/g')
	"$@"
    else
	set -- $(echo "$@" | sed 's/\\\\\([bcfnrtv0]\)/\\\1/g;s/[]\[\\\*]/\\&/g')
	$beam_rsh "$@"
    fi
}

runhook() {
    local hook_list
  
    eval hook_list=\$$1
    for hook in $hook_list
    do
	$hook
    done
}
 
print_version() {
    name=$(basename $0)
    cat <<EOF
$name (@PACKAGE_NAME@) @PACKAGE_VERSION@
Copyright (C) 2012 Sergey Poznyakoff
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
EOF
    exit 0
}

wtf() {
    l=$(echo "${1#beam-}"|sed "s|.|.|g")
    s=$(echo "                " | sed "s|$l|${1#beam-}|")
    shift
    echo "    $s $@"
}

dry_mail() {
    echo "============================================================="
    cat -
    echo "============================================================="
}

# mail_report FILE
mail_report() {
    : ${backup_mailer_program:=/usr/sbin/sendmail -oi -t -F $backup_sender_email}
    if [ -n "$dry_run" ]; then
	echo "Sending mail using $backup_mailer_program"
	backup_mailer_program=dry_mail
    fi
    if [ -z "$backup_sender_email" ]; then
	backup_sender_email=root@$(hostname)
    fi
    case $backup_sender_email in
	"<"*) ;;
	*)    backup_sender_email="<$backup_sender_email>"
    esac
    if [ -n "$backup_sender_personal" ]; then
	case $backup_sender_personal in
	    \"*) ;;
	    *) backup_sender_personal="\"$backup_sender_personal\""
	esac
	backup_sender_personal="$backup_sender_personal "
    fi
    if [ -z "$backup_report_subject" ]; then
	backup_report_subject="Backup of $(hostname) on $(date)"
    fi
    test -n "$backup_report_signature" &&
        echo "$backup_report_signature" >> $report
    (cat - <<EOF
From: ${backup_sender_personal}$backup_sender_email
To: $backup_notify_email
Subject: $backup_report_subject
X-Beam-Items: $backup_items
X-Beam-Round: $round
X-Beam-Level: $level
EOF
     if [ -n "$backup_report_headers" ]; then
	 echo "$backup_report_headers"
     fi
     echo ""
     if [ -n "$backup_report_intro" ]; then
	 echo "$backup_report_intro"
     fi
     cat $report
    ) | $backup_mailer_program
}

beam_logrotate() {
    local conf=/tmp/beam-logrotate.conf u
    if test -z "$backup_logrotate_conf"; then
	backup_logrotate_conf="weekly
rotate 4
"
    fi
    u=$(umask)
    umask 077
    cat > $conf <<EOF
$backup_logfile {
$backup_logrotate_conf
missingok
}
EOF
    umask $u
    test -d @LOCALSTATEDIR@/lib/beam || mkdir @LOCALSTATEDIR@/lib/beam
    logrotate ${dry_run+-d} $verbose --state @LOCALSTATEDIR@/lib/beam/logrotate.state $conf
    rm $conf
}