postinst

#!/bin/sh
# Copyright © 2003, 2005  Recai Oktaş <roktas@omu.edu.tr>
#             2014, 2015 Roger Kalt  <roger.kalt@gmail.com>
#
# Licensed under the GNU General Public License, version 2.
# See the file `http://www.gnu.org/copyleft/gpl.txt'.

set -e

# taken from Debian's Developer's Reference, 6.4
pathfind() {
    OLDIFS="$IFS"
    IFS=:
    for p in $PATH; do
        if [ -x "$p/$*" ]; then
            IFS="$OLDIFS"
            return 0
        fi
    done
    IFS="$OLDIFS"
    return 1
}

if [ "$1" != "configure" ]; then
	echo "postinst called with unknown argument '$1'" >&2
	exit 0
fi

# ELOG root.
SRVDIR=/var/lib/elog

# Welcome subject to check for a previous install.
WELCOME_SUBJECT="Welcome to ELOG"



# manually register elog service and install the links since dh_installinit is not used
if pathfind update-rc.d; then
	update-rc.d elog defaults >/dev/null
fi

#if [ "$2" ]; then   // I have no idea what the $2 argument could be given for?
if [ -d $SRVDIR/logbooks ]; then
	# Start daemon.
	if pathfind invoke-rc.d; then
		invoke-rc.d elog start
	else
		if [ -x /etc/init.d/elog ]; then
			/etc/init.d/elog start
		fi
	fi || true

	# No bother anymore, if this is not a fresh install.
	exit 0
fi

if ! getent passwd elog >/dev/null 2>&1; then
	echo -n "Creating user/group 'elog'" >&2
	adduser --quiet --system --group --no-create-home \
	--disabled-password --disabled-login \
	--shell /bin/false --home $SRVDIR elog
	echo "."
fi

if [ ! -d $SRVDIR/logbooks ]; then
	echo "Creating logbook directory '$SRVDIR/logbooks'" >&2
	install -d $SRVDIR/logbooks
fi

# Touch the ownerships.
chown -R elog:elog $SRVDIR
# see http://webapps-common.alioth.debian.org/draft/html/ch-issues.html section 3.2.1
chown root:elog /etc/elog.conf
chmod 660 /etc/elog.conf

# Now, setup ELOG port...

# Stolen from 'freenet-unstable', slightly modified.
is_freeport()
{
	# Pattern will fail to detect IPv6 bindings.
	! LC_ALL=C /bin/netstat -tnl 2>/dev/null | \
	egrep "tcp +[0-9]+ +[0-9]+ +[0-9]+\.[0-9]+\.[0-9]+\.[0-9]:$1 " >/dev/null
}

# Prints a welcome message for new users.
welcome()
{
	cat <<EOF
Congratulations for installing ELOG sucessfully!

This is a demo entry to ensure the elogd server is working correctly.
Click "New" to add new pages and "Delete" to delete this page.

See the html manual in "/usr/share/doc/elog" for
detailed instructions.  You can reach the manual from "doc-base".
EOF
}

# Get default port.
PORT=`awk 'tolower($1) == "port" { print $3 }' /etc/elog.conf`
if [ -z "$PORT" ]; then
	PORT=80
fi

# Search a free port.  Idea stolen from 'freenet-unstable'.  Since it is not
# mandatory to do this, just check the existence of 'netstat'.  No need to
# create a package dependency on 'net-tools'.
if pathfind netstat; then
	if is_freeport $PORT; then
		good_port="yes"
	else
		echo "Port '$PORT' is not free, checking the near ports..." >&2

		# First try to find the PORT in a memorizable range.
		for try in `seq $(($PORT + 1)) $(($PORT + 10))`; do
			echo -n "Checking $try... "
			is_freeport $try && { echo "free" >&2; good_port="yes"; break; }
			echo "not free" >&2
		done

		# Couldn't find?  Pick up a random PORT.
		if [ "$good_port" != "yes" ]; then
			echo -n "No free near ports, searching a random free port..." >&2
			num_try=50
			while [ $num_try -gt 0 ]; do
				my_random=$(dd if=/dev/urandom bs=1 count=10 2>/dev/null | cksum | cut -d' ' -f1)
				try=$(($my_random % 55535 + 10000))
				is_freeport $try && \
					{ echo " found $try" >&2; good_port="yes"; break; }
				num_try=$(($num_try - 1))
				echo -n "." >&2
			done
		fi

		if [ "$good_port" = "yes" ]; then
			PORT=$try
			# OK.  Save this validated port.
			tempfile="${TMPDIR:-/tmp}/elog.conf.$$"
			awk 'tolower($1) == "port" \
				{ $0 = "port = '"$PORT"' ; Automatically added in installation." }\
				{ print }' /etc/elog.conf >$tempfile
			mv -f $tempfile /etc/elog.conf
		else
			echo "$0: could not find a free port" >&2
			echo "You must configure it manually." >&2
		fi
	fi

else
	# Nearly impossible case for a healthy Debian box.
	echo "$0: can't exec 'netstat' to check for a free port" >&2
	echo "You must configure it manually." >&2
fi

# Configuration has been done, start daemon.
if [ -x /etc/init.d/elog ]; then
	
	if pathfind invoke-rc.d; then
		invoke-rc.d elog start
	else
		/etc/init.d/elog start
	fi || \
	{
		echo "$0: couldn't start ELOG; please start it later manually" >&2
		exit 0
	}

	# Wait a second to settled down.
	sleep 1
fi

# Submit a welcome log for the first time users.
if [ "$good_port" = "yes" -a -d $SRVDIR/logbooks/demo ] \
   && ! grep -sq "^Subject: *$WELCOME_SUBJECT$" $SRVDIR/logbooks/demo/*; then

	echo -n "Submitting a test message... " >&2
	# Piping only works for the 'elog' versions >= 2.3.8.
	welcome | \
	elog -h localhost -p $PORT -l demo \
	     -a subject="$WELCOME_SUBJECT" \
	     -a author="ELOG maintainer" \
	     -a type="Routine" \
	     -a category="General" >&2 || true
fi

# Always inform about the URL.

URL='http://localhost'
# Exclude default HTTP port if used.
if [ "$PORT" != "80" ]; then
	URL="$URL:$PORT"
fi

echo "ELOG is configured to reach from '$URL'." >&2

exit 0

# vim:ai:sts=8:sw=8:
elog 3.1.1-1-1 / postinst
