includes/historyblob/HistoryBlobCurStub.php

   1 <?php
   2 /**
   3  * Efficient concatenated text storage.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 /**
  24  * To speed up conversion from 1.4 to 1.5 schema, text rows can refer to the
  25  * leftover cur table as the backend. This avoids expensively copying hundreds
  26  * of megabytes of data during the conversion downtime.
  27  *
  28  * Serialized HistoryBlobCurStub objects will be inserted into the text table
  29  * on conversion if $wgLegacySchemaConversion is set to true.
  30  */
  31 class HistoryBlobCurStub {
  32         /** @var int */
  33         public $mCurId;
  34
  35         /**
  36          * @param int $curid The cur_id pointed to
  37          */
  38         function __construct( $curid = 0 ) {
  39                 $this->mCurId = $curid;
  40         }
  41
  42         /**
  43          * Sets the location (cur_id) of the main object to which this object
  44          * points
  45          *
  46          * @param int $id
  47          */
  48         function setLocation( $id ) {
  49                 $this->mCurId = $id;
  50         }
  51
  52         /**
  53          * @return string|bool
  54          */
  55         function getText() {
  56                 $dbr = wfGetDB( DB_REPLICA );
  57                 $row = $dbr->selectRow( 'cur', [ 'cur_text' ], [ 'cur_id' => $this->mCurId ] );
  58                 if ( !$row ) {
  59                         return false;
  60                 }
  61                 return $row->cur_text;
  62         }
  63 }
  64
  65 // phpcs:ignore Generic.CodeAnalysis.UnconditionalIfStatement.Found
  66 if ( false ) {
  67         // Blobs generated by MediaWiki < 1.5 on PHP 4 were serialized with the
  68         // class name coerced to lowercase. We can improve efficiency by adding
  69         // autoload entries for the lowercase variants of these classes (T166759).
  70         // The code below is never executed, but it is picked up by the AutoloadGenerator
  71         // parser, which scans for class_alias() calls.
  72         class_alias( HistoryBlobCurStub::class, 'historyblobcurstub' );
  73 }