includes/class_mo.php

   1 <?php
   2 /*=====================================================================*\
   3 || ###################################################################
   4 || # Bugdar
   5 || # Copyright ©2002-2007 Blue Static
   6 || #
   7 || # This program is free software; you can redistribute it and/or modify
   8 || # it under the terms of the GNU General Public License as published by
   9 || # the Free Software Foundation; version 2 of the License.
  10 || #
  11 || # This program is distributed in the hope that it will be useful, but
  12 || # WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13 || # or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  14 || # more details.
  15 || #
  16 || # You should have received a copy of the GNU General Public License along
  17 || # with this program; if not, write to the Free Software Foundation, Inc.,
  18 || # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
  19 || ###################################################################
  20 \*=====================================================================*/
  21
  22 /**
  23  * Message Object File Reader (.mo reader)
  24  *
  25  * Reads a MO file that is used by gettext but without needing the gettext
  26  * extension. The format is detailed here:
  27  * http://www.gnu.org/software/gettext/manual/html_node/MO-Files.html
  28  *
  29  * @author              rsesek
  30  * @copyright   Copyright (c)2006 - 2008, Blue Static
  31  * @version             $Revision$
  32  * @package             Bugdar
  33  *
  34  */
  35 class MOReader
  36 {
  37         /**
  38          * The name of the file to use
  39          * @var string
  40          */
  41         var $filename;
  42
  43         /**
  44          * The file pointer of the MO file
  45          * @var resource
  46          */
  47         var $file = null;
  48
  49         /**
  50          * Is the MO file a big endian one?
  51          * @var boolean
  52          */
  53         var $bigEndian = false;
  54
  55         /**
  56          * The string table as an array
  57          * @var array
  58          */
  59         var $strings = array();
  60
  61         /**
  62          * Creates a new MOReader given a path to a MO file
  63          */
  64         function MOReader($filename)
  65         {
  66                 $this->filename = $filename;
  67                 $this->_loadFile();
  68         }
  69
  70         /**
  71          * Returns the translated string for T, or the original if none exists
  72          *
  73          * @param       string  Native string to look up a translation for
  74          *
  75          * @return      string
  76          */
  77         function T($str)
  78         {
  79                 if (empty($this->strings[$str]))
  80                 {
  81                         return $str;
  82                 }
  83                 return $this->strings[$str];
  84         }
  85
  86         /**
  87          * Reads $size number of bytes
  88          *
  89          * @param       integer Number of bytes to read
  90          *
  91          * @return      string
  92          */
  93         function _readBytes($size)
  94         {
  95                 $stream = fread($this->file, 4 * $size);
  96                 if ($this->bigEndian)
  97                 {
  98                         return unpack('N' . $size, $stream);
  99                 }
 100                 else
 101                 {
 102                         return unpack('V' . $size, $stream);
 103                 }
 104         }
 105
 106         /**
 107          * Lodas the MO data information into the stirng table
 108          */
 109         function _loadFile()
 110         {
 111                 global $bugsys;
 112
 113                 $this->file = @fopen($this->filename, 'r');
 114                 if (!$this->file)
 115                 {
 116                         BSApp::debug("could not open MO file {$this->filename}");
 117                         return;
 118                 }
 119
 120                 // read the magic number
 121                 $stream = $this->_readBytes(1);
 122                 $stream = dechex($stream[1]);
 123                 if ($stream == '950412de')
 124                 {
 125                         $this->bigEndian = false;
 126                 }
 127                 else if ($stream == 'de120495')
 128                 {
 129                         $this->bigEndian = true;
 130                 }
 131                 else
 132                 {
 133                         throw new Exception('Invalid MO file format');
 134                 }
 135
 136                 // read the revision (unused in MOs)
 137                 $this->_readBytes(1);
 138
 139                 // read the number of strings
 140                 $count = $this->_readBytes(1);
 141                 $count = $count[1];
 142
 143                 // get the start positions of the original and translated tables
 144                 $offsetO = $this->_readBytes(1);
 145                 $offsetT = $this->_readBytes(1);
 146
 147                 fseek($this->file, $offsetO[1]);
 148                 $tableO = $this->_readBytes(2 * $count);
 149                 fseek($this->file, $offsetT[1]);
 150                 $tableT = $this->_readBytes(2 * $count);
 151
 152                 for ($i = 0; $i < $count; $i++)
 153                 {
 154                         if ($tableO[$i * 2 + 1] > 0)
 155                         {
 156                                 fseek($this->file, $tableO[$i * 2 + 2]);
 157                                 $O = fread($this->file, $tableO[$i * 2 + 1]);
 158                         }
 159
 160                         if ($tableT[$i * 2 + 1] > 0)
 161                         {
 162                                 fseek($this->file, $tableT[$i * 2 + 2]);
 163                                 $this->strings[$O] = fread($this->file, $tableT[$i * 2 + 1]);
 164                         }
 165                 }
 166
 167                 fclose($this->file);
 168         }
 169 }
 170
 171 /*=====================================================================*\
 172 || ###################################################################
 173 || # $HeadURL$
 174 || # $Id$
 175 || ###################################################################
 176 \*=====================================================================*/
 177 ?>