gnu-social/lib/daemon.php

167 lines
4.0 KiB
PHP

<?php
/**
* StatusNet - a distributed open-source microblogging tool
* Copyright (C) 2008, 2009, StatusNet, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
if (!defined('LACONICA')) {
exit(1);
}
class Daemon
{
var $daemonize = true;
var $_id = 'generic';
function __construct($daemonize = true)
{
$this->daemonize = $daemonize;
}
function name()
{
return null;
}
function get_id()
{
return $this->_id;
}
function set_id($id)
{
$this->_id = $id;
}
function background()
{
$pid = pcntl_fork();
if ($pid < 0) { // error
common_log(LOG_ERR, "Could not fork.");
return false;
} else if ($pid > 0) { // parent
common_log(LOG_INFO, "Successfully forked.");
exit(0);
} else { // child
return true;
}
}
function alreadyRunning()
{
$pidfilename = $this->pidFilename();
if (!$pidfilename) {
return false;
}
if (!file_exists($pidfilename)) {
return false;
}
$contents = file_get_contents($pidfilename);
if (posix_kill(trim($contents), 0)) {
return true;
} else {
return false;
}
}
function writePidFile()
{
$pidfilename = $this->pidFilename();
if (!$pidfilename) {
return false;
}
return file_put_contents($pidfilename, posix_getpid() . "\n");
}
function clearPidFile()
{
$pidfilename = $this->pidFilename();
if (!$pidfilename) {
return false;
}
return unlink($pidfilename);
}
function pidFilename()
{
$piddir = common_config('daemon', 'piddir');
if (!$piddir) {
return null;
}
$name = $this->name();
if (!$name) {
return null;
}
return $piddir . '/' . $name . '.pid';
}
function changeUser()
{
$username = common_config('daemon', 'user');
if ($username) {
$user_info = posix_getpwnam($username);
if (!$user_info) {
common_log(LOG_WARNING,
'Ignoring unknown user for daemon: ' . $username);
} else {
common_log(LOG_INFO, "Setting user to " . $username);
posix_setuid($user_info['uid']);
}
}
$groupname = common_config('daemon', 'group');
if ($groupname) {
$group_info = posix_getgrnam($groupname);
if (!$group_info) {
common_log(LOG_WARNING,
'Ignoring unknown group for daemon: ' . $groupname);
} else {
common_log(LOG_INFO, "Setting group to " . $groupname);
posix_setgid($group_info['gid']);
}
}
}
function runOnce()
{
if ($this->alreadyRunning()) {
common_log(LOG_INFO, $this->name() . ' already running. Exiting.');
exit(0);
}
if ($this->daemonize) {
common_log(LOG_INFO, 'Backgrounding daemon "'.$this->name().'"');
$this->background();
}
$this->writePidFile();
$this->changeUser();
$this->run();
$this->clearPidFile();
}
function run()
{
return true;
}
}