friendica/src/System/Daemon.php
2025-01-02 12:54:39 +01:00

210 lines
5.1 KiB
PHP

<?php
// Copyright (C) 2010-2025, the Friendica project
// SPDX-FileCopyrightText: 2010-2024 the Friendica project
//
// SPDX-License-Identifier: AGPL-3.0-or-later
namespace Friendica\System;
use Friendica\Database\Database;
use Psr\Log\LoggerInterface;
/**
* class for direct interacting with the daemon commands
*/
final class Daemon
{
private LoggerInterface $logger;
private Database $dba;
private ?string $pidfile = null;
private ?int $pid = null;
/**
* The PID of the current daemon (null if either not set or not found)
*
* @return int|null
*/
public function getPid(): ?int
{
return $this->pid;
}
/**
* The path to the PID file (null if not set)
*
* @return string|null
*/
public function getPidfile(): ?string
{
return $this->pidfile;
}
public function __construct(LoggerInterface $logger, Database $dba)
{
$this->logger = $logger;
$this->dba = $dba;
}
/**
* Initialize the current daemon class with a given PID file
*
* @param string|null $pidfile the path to the PID file - using a given path if not directly set here
*
* @return void
*/
public function init(string $pidfile = null): void
{
if (!empty($pidfile)) {
$this->pid = null;
$this->pidfile = $pidfile;
}
if (!empty($this->pid)) {
return;
}
if (is_readable($this->pidfile)) {
$this->pid = intval(file_get_contents($this->pidfile));
}
}
/**
* Starts the daemon
*
* @param callable $daemonLogic the business logic of the daemon
* @param bool $foreground true, if started in foreground, otherwise spawned in the background
*
* @return bool true, if successfully started, otherwise false
*/
public function start(callable $daemonLogic, bool $foreground = false): bool
{
$this->init();
if (!empty($this->pid)) {
$this->logger->notice('process is already running', ['pid' => $this->pid, 'pidfile' => $this->pidfile]);
return false;
}
$this->logger->notice('starting daemon', ['pid' => $this->pid, 'pidfile' => $this->pidfile]);
if (!$foreground) {
$this->dba->disconnect();
// fork a daemon process
$this->pid = pcntl_fork();
if ($this->pid < 0) {
$this->logger->warning('Could not fork daemon');
return false;
} elseif ($this->pid) {
// The parent process continues here
if (!file_put_contents($this->pidfile, $this->pid)) {
$this->logger->warning('Could not store pid file', ['pid' => $this->pid, 'pidfile' => $this->pidfile]);
posix_kill($this->pid, SIGTERM);
return false;
}
$this->logger->notice('Child process started', ['pid' => $this->pid, 'pidfile' => $this->pidfile]);
return true;
}
// We now are in the child process
register_shutdown_function(function (): void {
posix_kill(posix_getpid(), SIGTERM);
posix_kill(posix_getpid(), SIGHUP);
});
// Make the child the main process, detach it from the terminal
if (posix_setsid() < 0) {
return true;
}
// Closing all existing connections with the outside
fclose(STDIN);
// And now connect the database again
$this->dba->connect();
}
// Just to be sure that this script really runs endlessly
set_time_limit(0);
$daemonLogic();
return true;
}
/**
* Checks, if the current daemon is running
*
* @return bool true, if the daemon is running, otherwise false (f.e no PID found, no PID file found, PID is not bound to a running process))
*/
public function isRunning(): bool
{
$this->init();
if (empty($this->pid)) {
$this->logger->notice("Pid wasn't found");
if (is_readable($this->pidfile)) {
unlink($this->pidfile);
$this->logger->notice("Pidfile removed", ['pidfile' => $this->pidfile]);
}
return false;
}
if (posix_kill($this->pid, 0)) {
$this->logger->notice("daemon process is running");
return true;
} else {
unlink($this->pidfile);
$this->logger->notice("daemon process isn't running");
return false;
}
}
/**
* Stops the daemon, if running
*
* @return bool true, if the daemon was successfully stopped or is already stopped, otherwise false
*/
public function stop(): bool
{
$this->init();
if (empty($this->pid)) {
$this->logger->notice("Pidfile wasn't found", ['pidfile' => $this->pidfile]);
return true;
}
if (!posix_kill($this->pid, SIGTERM)) {
$this->logger->warning("Cannot kill the given PID", ['pid' => $this->pid, 'pidfile' => $this->pidfile]);
return false;
}
if (!unlink($this->pidfile)) {
$this->logger->warning("Cannot delete the given PID file", ['pid' => $this->pid, 'pidfile' => $this->pidfile]);
return false;
}
$this->logger->notice('daemon process was killed', ['pid' => $this->pid, 'pidfile' => $this->pidfile]);
return true;
}
/**
* Sets the current daemon to sleep and checks the status afterward
*
* @param int $duration the duration of time for sleeping (in milliseconds)
*
* @return void
*/
public function sleep(int $duration)
{
usleep($duration);
$this->pid = pcntl_waitpid(-1, $status, WNOHANG);
if ($this->pid > 0) {
$this->logger->info('Children quit via pcntl_waitpid', ['pid' => $this->pid, 'status' => $status]);
}
}
}