core/CliMulti/Process.php


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208

<?php
/**
 * Piwik - free/libre analytics platform
 *
 * @link http://piwik.org
 * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
 */
namespace Piwik\CliMulti;

use Piwik\CliMulti;
use Piwik\Filesystem;
use Piwik\SettingsServer;

/**
 * There are three different states
 * - PID file exists with empty content: Process is created but not started
 * - PID file exists with the actual process PID as content: Process is runnning
 * - PID file does not exist: Process is marked as finished
 *
 * Class Process
 */
class Process
{
    private $pidFile = '';
    private $timeCreation = null;
    private $isSupported = null;

    public function __construct($pid)
    {
        if (!Filesystem::isValidFilename($pid)) {
            throw new \Exception('The given pid has an invalid format');
        }

        $pidDir = CliMulti::getTmpPath();
        Filesystem::mkdir($pidDir);

        $this->isSupported  = self::isSupported();
        $this->pidFile      = $pidDir . '/' . $pid . '.pid';
        $this->timeCreation = time();

        $this->markAsNotStarted();
    }

    private function markAsNotStarted()
    {
        $content = $this->getPidFileContent();

        if ($this->doesPidFileExist($content)) {
            return;
        }

        $this->writePidFileContent('');
    }

    public function hasStarted($content = null)
    {
        if (is_null($content)) {
            $content = $this->getPidFileContent();
        }

        if (!$this->doesPidFileExist($content)) {
            // process is finished, this means there was a start before
            return true;
        }

        if ('' === trim($content)) {
            // pid file is overwritten by startProcess()
            return false;
        }

        // process is probably running or pid file was not removed
        return true;
    }

    public function hasFinished()
    {
        $content = $this->getPidFileContent();

        return !$this->doesPidFileExist($content);
    }

    public function getSecondsSinceCreation()
    {
        return time() - $this->timeCreation;
    }

    public function startProcess()
    {
        $this->writePidFileContent(getmypid());
    }

    public function isRunning()
    {
        $content = $this->getPidFileContent();

        if (!$this->doesPidFileExist($content)) {
            return false;
        }

        if ($this->isProcessStillRunning($content)) {
            return true;
        }

        if ($this->hasStarted($content)) {
            $this->finishProcess();
        }

        return false;
    }

    public function finishProcess()
    {
        Filesystem::deleteFileIfExists($this->pidFile);
    }

    private function doesPidFileExist($content)
    {
        return false !== $content;
    }

    private function isProcessStillRunning($content)
    {
        if (!$this->isSupported) {
            return true;
        }

        $lockedPID   = trim($content);
        $runningPIDs = explode("\n", trim( `ps -e | awk '{print $1}'` ));

        return !empty($lockedPID) && in_array($lockedPID, $runningPIDs);
    }

    private function getPidFileContent()
    {
        return @file_get_contents($this->pidFile);
    }

    private function writePidFileContent($content)
    {
        file_put_contents($this->pidFile, $content);
    }

    public static function isSupported()
    {
        if (SettingsServer::isWindows()) {
            return false;
        }

        if (self::shellExecFunctionIsDisabled()) {
            return false;
        }

        if (self::isSystemNotSupported()) {
            return false;
        }

        if(!self::isProcFSMounted()) {
            return false;
        }

        if (static::commandExists('ps') && self::returnsSuccessCode('ps') && self::commandExists('awk')) {
            return true;
        }

        return false;
    }

    private static function isSystemNotSupported()
    {
        $uname = shell_exec('uname -a');
        if(strpos($uname, 'synology') !== false) {
            return true;
        }
        return false;
    }

    private static function shellExecFunctionIsDisabled()
    {
        $command = 'shell_exec';
        $disabled = explode(',', ini_get('disable_functions'));
        $disabled = array_map('trim', $disabled);
        return in_array($command, $disabled);
    }

    private static function returnsSuccessCode($command)
    {
        $exec = $command . ' > /dev/null 2>&1; echo $?';
        $returnCode = shell_exec($exec);
        $returnCode = trim($returnCode);
        return 0 == (int) $returnCode;
    }

    private static function commandExists($command)
    {
        $result = shell_exec('which ' . escapeshellarg($command) . ' 2> /dev/null');

        return !empty($result);
    }

    /**
     * ps -e requires /proc
     * @return bool
     */
    private static function isProcFSMounted() 
    {
        return is_resource(@fopen('/proc', 'r'));
    }
}