xref: /dokuwiki/inc/ErrorHandler.php (revision cb4cefebb32128c1e6893c596b119ef03d82a7f2) 
1<?php
2
3namespace dokuwiki;
4
5class ErrorHandler
6{
7
8    /**
9     * Register the default error handling
10     */
11    public static function register()
12    {
13        set_error_handler([ErrorHandler::class, 'errorConverter']);
14        if (!defined('DOKU_UNITTEST')) {
15            set_exception_handler([ErrorHandler::class, 'fatalException']);
16            register_shutdown_function([ErrorHandler::class, 'fatalShutdown']);
17        }
18    }
19
20    /**
21     * Default Exception handler to show a nice user message before dieing
22     *
23     * The exception is logged to the error log
24     *
25     * @param \Throwable $e
26     */
27    public static function fatalException($e)
28    {
29        $plugin = self::guessPlugin($e);
30        $title = hsc(get_class($e) . ': ' . $e->getMessage());
31        $msg = 'An unforeseen error has occured. This is most likely a bug somewhere.';
32        if ($plugin) $msg .= ' It might be a problem in the ' . $plugin . ' plugin.';
33        $logged = self::logException($e)
34            ? 'More info has been written to the DokuWiki _error.log'
35            : $e->getFile() . ':' . $e->getLine();
36
37        echo <<<EOT
38<!DOCTYPE html>
39<html>
40<head><title>$title</title></head>
41<body style="font-family: Arial, sans-serif">
42    <div style="width:60%; margin: auto; background-color: #fcc;
43                border: 1px solid #faa; padding: 0.5em 1em;">
44        <h1 style="font-size: 120%">$title</h1>
45        <p>$msg</p>
46        <p>$logged</p>
47    </div>
48</body>
49</html>
50EOT;
51    }
52
53    /**
54     * Convenience method to display an error message for the given Exception
55     *
56     * @param \Throwable $e
57     * @param string $intro
58     */
59    public static function showExceptionMsg($e, $intro = 'Error!')
60    {
61        $msg = hsc($intro) . '<br />' . hsc(get_class($e) . ': ' . $e->getMessage());
62        if (self::logException($e)) $msg .= '<br />More info is available in the _error.log';
63        msg($msg, -1);
64    }
65
66    /**
67     * Default error handler to convert old school warnings, notices, etc to exceptions
68     *
69     * You should not need to call this directly!
70     *
71     * @param int $errno
72     * @param string $errstr
73     * @param string $errfile
74     * @param int $errline
75     * @return bool
76     * @throws \ErrorException
77     */
78    public static function errorConverter($errno, $errstr, $errfile, $errline)
79    {
80
81        if (!(error_reporting() & $errno)) {
82            // This error code is not included in error_reporting, so let it fall
83            // through to the standard PHP error handler
84            return false;
85        }
86
87        throw new \ErrorException($errstr, 0, $errno, $errfile, $errline);
88    }
89
90    /**
91     * Last resort to handle fatal errors that still can't be cought
92     */
93    public static function fatalShutdown()
94    {
95        $error = error_get_last();
96        // Check if it's a core/fatal error, otherwise it's a normal shutdown
97        if (
98            $error !== null &&
99            in_array(
100                $error['type'],
101                [
102                    E_ERROR,
103                    E_CORE_ERROR,
104                    E_COMPILE_ERROR,
105                ]
106            )
107        ) {
108            self::fatalException(
109                new \ErrorException($error['message'], 0, $error['type'], $error['file'], $error['line'])
110            );
111        }
112    }
113
114    /**
115     * Log the given exception to the error log
116     *
117     * @param \Throwable $e
118     * @return bool false if the logging failed
119     */
120    public static function logException($e)
121    {
122        global $conf;
123
124        $log = join("\t", [
125                gmdate('c'),
126                get_class($e),
127                $e->getFile() . '(' . $e->getLine() . ')',
128                $e->getMessage(),
129            ]) . "\n";
130        $log .= $e->getTraceAsString() . "\n";
131        return io_saveFile($conf['cachedir'] . '/_error.log', $log, true);
132    }
133
134    /**
135     * Checks the the stacktrace for plugin files
136     *
137     * @param \Throwable $e
138     * @return false|string
139     */
140    protected static function guessPlugin($e)
141    {
142        foreach ($e->getTrace() as $line) {
143            if (
144                isset($line['class']) &&
145                preg_match('/\w+?_plugin_(\w+)/', $line['class'], $match)
146            ) {
147                return $match[1];
148            }
149
150            if (
151                isset($line['file']) &&
152                preg_match('/lib\/plugins\/(\w+)\//', str_replace('\\', '/', $line['file']), $match)
153            ) {
154                return $match[1];
155            }
156        }
157
158        return false;
159    }
160}
161