lock: Cleanup lock files

[people/ms/network.git] / src / functions / functions.lock

#!/bin/bash
###############################################################################
#                                                                             #
# IPFire.org - A linux based firewall                                         #
# Copyright (C) 2012  Michael Tremer & Christian Schmidt                      #
#                                                                             #
# This program 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 of the License, or           #
# (at your option) any later version.                                         #
#                                                                             #
# This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.       #
#                                                                             #
###############################################################################

lock() {
	local lock="${1}"
	shift

	# Move locks with name only into lock directory
	if [ "${lock:0:1}" != "/" ]; then
		lock="${LOCK_DIR}/${lock}"
	fi

	local timeout="60"
	local ret=0

	# Make partent directory
	make_parent_directory "${lock}"

	(
		log DEBUG "Trying to acquire lock ${lock}"

		# Try to acquire lock on fd 9
		if ! flock -w "${timeout}" 9; then
			log ERROR "Failed to acquire lock ${lock} after ${timeout} seconds"
			exit ${EXIT_ERROR}
		fi

		log DEBUG "Acquired lock ${lock}"

		# Remember return code
		ret=${EXIT_OK}

		# Run command
		"$@" || ret=$?

		log DEBUG "Released lock ${lock}"

		exit ${ret}
	) 9>${lock} || ret=$?

	# Cleanup log file
	file_delete "${lock}"

	return ${ret}
}