1<?php
2
3/*
4 * This file is part of the Symfony package.
5 *
6 * (c) Fabien Potencier <fabien@symfony.com>
7 *
8 * For the full copyright and license information, please view the LICENSE
9 * file that was distributed with this source code.
10 */
11
12namespace Symfony\Component\Translation\Loader;
13
14use Symfony\Component\Translation\Exception\InvalidResourceException;
15
16/**
17 * @copyright Copyright (c) 2010, Union of RAD http://union-of-rad.org (http://lithify.me/)
18 */
19class MoFileLoader extends FileLoader
20{
21    /**
22     * Magic used for validating the format of a MO file as well as
23     * detecting if the machine used to create that file was little endian.
24     */
25    const MO_LITTLE_ENDIAN_MAGIC = 0x950412de;
26
27    /**
28     * Magic used for validating the format of a MO file as well as
29     * detecting if the machine used to create that file was big endian.
30     */
31    const MO_BIG_ENDIAN_MAGIC = 0xde120495;
32
33    /**
34     * The size of the header of a MO file in bytes.
35     */
36    const MO_HEADER_SIZE = 28;
37
38    /**
39     * Parses machine object (MO) format, independent of the machine's endian it
40     * was created on. Both 32bit and 64bit systems are supported.
41     *
42     * {@inheritdoc}
43     */
44    protected function loadResource($resource)
45    {
46        $stream = fopen($resource, 'r');
47
48        $stat = fstat($stream);
49
50        if ($stat['size'] < self::MO_HEADER_SIZE) {
51            throw new InvalidResourceException('MO stream content has an invalid format.');
52        }
53        $magic = unpack('V1', fread($stream, 4));
54        $magic = hexdec(substr(dechex(current($magic)), -8));
55
56        if (self::MO_LITTLE_ENDIAN_MAGIC == $magic) {
57            $isBigEndian = false;
58        } elseif (self::MO_BIG_ENDIAN_MAGIC == $magic) {
59            $isBigEndian = true;
60        } else {
61            throw new InvalidResourceException('MO stream content has an invalid format.');
62        }
63
64        // formatRevision
65        $this->readLong($stream, $isBigEndian);
66        $count = $this->readLong($stream, $isBigEndian);
67        $offsetId = $this->readLong($stream, $isBigEndian);
68        $offsetTranslated = $this->readLong($stream, $isBigEndian);
69        // sizeHashes
70        $this->readLong($stream, $isBigEndian);
71        // offsetHashes
72        $this->readLong($stream, $isBigEndian);
73
74        $messages = [];
75
76        for ($i = 0; $i < $count; ++$i) {
77            $pluralId = null;
78            $translated = null;
79
80            fseek($stream, $offsetId + $i * 8);
81
82            $length = $this->readLong($stream, $isBigEndian);
83            $offset = $this->readLong($stream, $isBigEndian);
84
85            if ($length < 1) {
86                continue;
87            }
88
89            fseek($stream, $offset);
90            $singularId = fread($stream, $length);
91
92            if (false !== strpos($singularId, "\000")) {
93                list($singularId, $pluralId) = explode("\000", $singularId);
94            }
95
96            fseek($stream, $offsetTranslated + $i * 8);
97            $length = $this->readLong($stream, $isBigEndian);
98            $offset = $this->readLong($stream, $isBigEndian);
99
100            if ($length < 1) {
101                continue;
102            }
103
104            fseek($stream, $offset);
105            $translated = fread($stream, $length);
106
107            if (false !== strpos($translated, "\000")) {
108                $translated = explode("\000", $translated);
109            }
110
111            $ids = ['singular' => $singularId, 'plural' => $pluralId];
112            $item = compact('ids', 'translated');
113
114            if (!empty($item['ids']['singular'])) {
115                $id = $item['ids']['singular'];
116                if (isset($item['ids']['plural'])) {
117                    $id .= '|'.$item['ids']['plural'];
118                }
119                $messages[$id] = stripcslashes(implode('|', (array) $item['translated']));
120            }
121        }
122
123        fclose($stream);
124
125        return array_filter($messages);
126    }
127
128    /**
129     * Reads an unsigned long from stream respecting endianness.
130     *
131     * @param resource $stream
132     * @param bool     $isBigEndian
133     *
134     * @return int
135     */
136    private function readLong($stream, $isBigEndian)
137    {
138        $result = unpack($isBigEndian ? 'N1' : 'V1', fread($stream, 4));
139        $result = current($result);
140
141        return (int) substr($result, -8);
142    }
143}
144