Handy gentoo auto update cron script

update_gentoo.sh

#!/bin/bash
#
# eix depended handy gentoo update cron script.
# * Prioritize portage upgrade if available.
# * Runs perl-cleaner for perl upgrade process.
# * Warns for reboot if pam upgraded.
# * Sends upgrade summary via mail.

#======================================================================================
# send mail configuration:
# If you want to recieve script output as a mail please set 'send_mail' to 1. Default 0.
# You need to have properly configured mail server with 'mail' command.
# If you use 'sendmail' you have to edit script otherwise script cannot send mail.
send_mail=0

# Adjust mail options:
mail_to="your@domain.tld"
mail_from="From: Gentoo System <root@domain.tld>"
mail_subject="Gentoo Update Informations"

# depclean configuration:
# Set depclean for excluding packages. In default gentoo-sources excluded.
exclude="--exclude gentoo-sources"

# etc-update configuration:
# If you want to update config files after update please set to -3.
# If you want to keep config files same and discard all updates set to -7.
# If you want to exit without doing anything set to -1. Default -1
keep_config="-1"
#======================================================================================

# Execution start time
ext_s=`date +%s`

converter() {
	h=$(bc <<< "${1}/3600")
	m=$(bc <<< "(${1}%3600)/60")
	s=$(bc <<< "${1}%60")
	printf "%02d:%02d:%05.2f\n" $h $m $s
}

# Check 'eix' is installed
if ! command -v eix > /dev/null 2>&1; then
        echo -e "You need to install necessary package first!"
        echo -e "emerge -a app-portage/eix"
        exit 1
fi

# Check is system able to send mail with 'mail' command
if ! command -v mail > /dev/null 2>&1; then
        send_mail=0
elif [[ "$send_mail" -eq 1 ]]; then
        tfile="/tmp/$$.$RANDOM.gentoo"
fi

# Sync packages and update db
echo "Syncing.."
eix-sync -q && updatedb

if eix --installed --upgrade | grep -q "[U]"; then
        echo "Updating gentoo.."
        if [[ "$send_mail" -eq 1 ]]; then
                # Get the list of upgradeable packages & send output to file
		echo "The following packages updated:" > "$tfile"
                echo "------------------------------------------------------" >> "$tfile"
                eix --installed --upgrade | grep -w "[U]" &>> "$tfile"
                echo "------------------------------------------------------" >> "$tfile"
        fi

        # Check portage needs to be upgraded first
        if eix --installed --upgrade | grep -q "sys-apps/portage"; then
                emerge --ask=n -u1 --quiet --quiet-build sys-apps/portage
                if [[ "$send_mail" -eq 1 ]]; then
                        echo "Portage Updated = Yes" >> "$tfile"
                fi
        elif [[ "$send_mail" -eq 1 ]]; then
                echo "Portage Updated = No" >> "$tfile"
        fi

        # Check perl will be upgraded too
        if eix --installed --upgrade | grep -q "dev-lang/perl"; then
                perl_cleaner=1
                if [[ "$send_mail" -eq 1 ]]; then
                        echo "Perl Updated = Yes" >> "$tfile"
                fi
        elif [[ "$send_mail" -eq 1 ]]; then
                echo "Perl Updated = No" >> "$tfile"
        fi
		
	# Check pam will be upgraded too, it needs reboot
	if eix --installed --upgrade | grep -q "sys-libs/pam"; then
		if [[ "$send_mail" -eq 1 ]]; then
			echo "Pam Updated = Yes --> REBOOT REQUIRED" >> "$tfile"
                fi
	elif [[ "$send_mail" -eq 1 ]]; then
		echo "Pam Updated = No" >> "$tfile"
	fi

        # Start the upgrade process
        emerge --ask=n --update --deep --changed-use --quiet --quiet-build --quiet-fail @world &&
        eselect news read > /dev/null 2>&1 &&
        emerge @preserved-rebuild --quiet &&
        revdep-rebuild -q &&

        # Start cleaning process
        emerge --depclean $exclude --quiet &&
        eclean -d distfiles > /dev/null 2>&1

        # Complete perl related processes
        if [[ -n "$perl_cleaner" ]]; then
                emerge --ask=n -uDN --complete-graph=y --with-bdeps=y --backtrack=100 --autounmask-keep-masks=y --quiet --quiet-build --quiet-fail @world &&
                perl-cleaner --all -q &&
                emerge @preserved-rebuild --quiet &&
                revdep-rebuild -q &&

                # Start cleaning process
                emerge --depclean $exclude --quiet &&
                eclean -d distfiles > /dev/null 2>&1
        fi

        # Finish the update process, set configs & env
        echo "$keep_config" | etc-update &&
        updatedb &&
        env-update > /dev/null 2>&1 &&
        source /etc/profile &&
        echo "Gentoo updated.."

        # Execution end time
        ext_f=`date +%s`

        # Calculate execution runtime
        runtime=$((ext_f-ext_s))

        # Send mail
        if [[ "$send_mail" -eq 1 ]]; then
                echo "------------------------------------------------------" >> "$tfile"
                echo "The update process took $(converter $runtime)." >> "$tfile"
                cat "$tfile" | mail -s "$mail_subject" -a "$mail_from" "$mail_to"
                trap "{ rm -f $tfile; }" EXIT
        fi
else
        echo "There is no update currently.."
        if [[ "$send_mail" -eq 1 ]]; then
                echo "There is no update currently.." | mail -s "$mail_subject" -a "$mail_from" "$mail_to"
                trap "{ rm -f $tfile; }" EXIT
        fi
fi