1<?php
2/**
3 * PHPTAL templating engine
4 *
5 * PHP Version 5
6 *
7 * @category HTML
8 * @package  PHPTAL
9 * @author   Kornel Lesiński <kornel@aardvarkmedia.co.uk>
10 * @license  http://www.gnu.org/licenses/lgpl.html GNU Lesser General Public License
11 * @version  SVN: $Id: $
12 * @link     http://phptal.org/
13 */
14
15class PHPTAL_ExceptionHandler
16{
17    private $encoding;
18    function __construct($encoding)
19    {
20        $this->encoding = $encoding;
21    }
22
23    /**
24     * PHP's default exception handler allows error pages to be indexed and can reveal too much information,
25     * so if possible PHPTAL sets up its own handler to fix this.
26     *
27     * Doesn't change exception handler if non-default one is set.
28     *
29     * @param Exception e exception to re-throw and display
30     *
31     * @return void
32     * @throws Exception
33     */
34    public static function handleException(Exception $e, $encoding)
35    {
36        // PHPTAL's handler is only useful on fresh HTTP response
37        if (PHP_SAPI !== 'cli' && !headers_sent()) {
38            $old_exception_handler = set_exception_handler(array(new PHPTAL_ExceptionHandler($encoding), '_defaultExceptionHandler'));
39
40            if ($old_exception_handler !== NULL) {
41                restore_exception_handler(); // if there's user's exception handler, let it work
42            }
43        }
44        throw $e; // throws instead of outputting immediately to support user's try/catch
45    }
46
47
48    /**
49     * Generates simple error page. Sets appropriate HTTP status to prevent page being indexed.
50     *
51     * @param Exception e exception to display
52     */
53    public function _defaultExceptionHandler($e)
54    {
55        if (!headers_sent()) {
56            header('HTTP/1.1 500 PHPTAL Exception');
57            header('Content-Type:text/html;charset='.$this->encoding);
58        }
59
60        $line = $e->getFile();
61        if ($e->getLine()) {
62            $line .= ' line '.$e->getLine();
63        }
64
65        if (ini_get('display_errors')) {
66            $title = get_class($e).': '.htmlspecialchars($e->getMessage());
67            $body = "<p><strong>\n".htmlspecialchars($e->getMessage()).'</strong></p>' .
68                    '<p>In '.htmlspecialchars($line)."</p><pre>\n".htmlspecialchars($e->getTraceAsString()).'</pre>';
69        } else {
70            $title = "PHPTAL Exception";
71            $body = "<p>This page cannot be displayed.</p><hr/>" .
72                    "<p><small>Enable <code>display_errors</code> to see detailed message.</small></p>";
73        }
74
75        echo "<!DOCTYPE html><html xmlns='http://www.w3.org/1999/xhtml'><head><style>body{font-family:sans-serif}</style><title>\n";
76        echo $title.'</title></head><body><h1>PHPTAL Exception</h1>'.$body;
77        error_log($e->getMessage().' in '.$line);
78        echo '</body></html>'.str_repeat('    ', 100)."\n"; // IE won't display error pages < 512b
79        exit(1);
80    }
81}
82