includes/cache/LocalisationCache.php

   1 <?php
   2 /**
   3  * Cache of the contents of localisation files.
   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 use Cdb\Exception as CdbException;
  24 use Cdb\Reader as CdbReader;
  25 use Cdb\Writer as CdbWriter;
  26
  27 /**
  28  * Class for caching the contents of localisation files, Messages*.php
  29  * and *.i18n.php.
  30  *
  31  * An instance of this class is available using Language::getLocalisationCache().
  32  *
  33  * The values retrieved from here are merged, containing items from extension
  34  * files, core messages files and the language fallback sequence (e.g. zh-cn ->
  35  * zh-hans -> en ). Some common errors are corrected, for example namespace
  36  * names with spaces instead of underscores, but heavyweight processing, such
  37  * as grammatical transformation, is done by the caller.
  38  */
  39 class LocalisationCache {
  40         const VERSION = 3;
  41
  42         /** Configuration associative array */
  43         private $conf;
  44
  45         /**
  46          * True if recaching should only be done on an explicit call to recache().
  47          * Setting this reduces the overhead of cache freshness checking, which
  48          * requires doing a stat() for every extension i18n file.
  49          */
  50         private $manualRecache = false;
  51
  52         /**
  53          * True to treat all files as expired until they are regenerated by this object.
  54          */
  55         private $forceRecache = false;
  56
  57         /**
  58          * The cache data. 3-d array, where the first key is the language code,
  59          * the second key is the item key e.g. 'messages', and the third key is
  60          * an item specific subkey index. Some items are not arrays and so for those
  61          * items, there are no subkeys.
  62          */
  63         protected $data = array();
  64
  65         /**
  66          * The persistent store object. An instance of LCStore.
  67          *
  68          * @var LCStore
  69          */
  70         private $store;
  71
  72         /**
  73          * A 2-d associative array, code/key, where presence indicates that the item
  74          * is loaded. Value arbitrary.
  75          *
  76          * For split items, if set, this indicates that all of the subitems have been
  77          * loaded.
  78          */
  79         private $loadedItems = array();
  80
  81         /**
  82          * A 3-d associative array, code/key/subkey, where presence indicates that
  83          * the subitem is loaded. Only used for the split items, i.e. messages.
  84          */
  85         private $loadedSubitems = array();
  86
  87         /**
  88          * An array where presence of a key indicates that that language has been
  89          * initialised. Initialisation includes checking for cache expiry and doing
  90          * any necessary updates.
  91          */
  92         private $initialisedLangs = array();
  93
  94         /**
  95          * An array mapping non-existent pseudo-languages to fallback languages. This
  96          * is filled by initShallowFallback() when data is requested from a language
  97          * that lacks a Messages*.php file.
  98          */
  99         private $shallowFallbacks = array();
 100
 101         /**
 102          * An array where the keys are codes that have been recached by this instance.
 103          */
 104         private $recachedLangs = array();
 105
 106         /**
 107          * All item keys
 108          */
 109         static public $allKeys = array(
 110                 'fallback', 'namespaceNames', 'bookstoreList',
 111                 'magicWords', 'messages', 'rtl', 'capitalizeAllNouns', 'digitTransformTable',
 112                 'separatorTransformTable', 'fallback8bitEncoding', 'linkPrefixExtension',
 113                 'linkTrail', 'linkPrefixCharset', 'namespaceAliases',
 114                 'dateFormats', 'datePreferences', 'datePreferenceMigrationMap',
 115                 'defaultDateFormat', 'extraUserToggles', 'specialPageAliases',
 116                 'imageFiles', 'preloadedMessages', 'namespaceGenderAliases',
 117                 'digitGroupingPattern', 'pluralRules', 'pluralRuleTypes', 'compiledPluralRules',
 118         );
 119
 120         /**
 121          * Keys for items which consist of associative arrays, which may be merged
 122          * by a fallback sequence.
 123          */
 124         static public $mergeableMapKeys = array( 'messages', 'namespaceNames',
 125                 'dateFormats', 'imageFiles', 'preloadedMessages'
 126         );
 127
 128         /**
 129          * Keys for items which are a numbered array.
 130          */
 131         static public $mergeableListKeys = array( 'extraUserToggles' );
 132
 133         /**
 134          * Keys for items which contain an array of arrays of equivalent aliases
 135          * for each subitem. The aliases may be merged by a fallback sequence.
 136          */
 137         static public $mergeableAliasListKeys = array( 'specialPageAliases' );
 138
 139         /**
 140          * Keys for items which contain an associative array, and may be merged if
 141          * the primary value contains the special array key "inherit". That array
 142          * key is removed after the first merge.
 143          */
 144         static public $optionalMergeKeys = array( 'bookstoreList' );
 145
 146         /**
 147          * Keys for items that are formatted like $magicWords
 148          */
 149         static public $magicWordKeys = array( 'magicWords' );
 150
 151         /**
 152          * Keys for items where the subitems are stored in the backend separately.
 153          */
 154         static public $splitKeys = array( 'messages' );
 155
 156         /**
 157          * Keys which are loaded automatically by initLanguage()
 158          */
 159         static public $preloadedKeys = array( 'dateFormats', 'namespaceNames' );
 160
 161         /**
 162          * Associative array of cached plural rules. The key is the language code,
 163          * the value is an array of plural rules for that language.
 164          */
 165         private $pluralRules = null;
 166
 167         /**
 168          * Associative array of cached plural rule types. The key is the language
 169          * code, the value is an array of plural rule types for that language. For
 170          * example, $pluralRuleTypes['ar'] = ['zero', 'one', 'two', 'few', 'many'].
 171          * The index for each rule type matches the index for the rule in
 172          * $pluralRules, thus allowing correlation between the two. The reason we
 173          * don't just use the type names as the keys in $pluralRules is because
 174          * Language::convertPlural applies the rules based on numeric order (or
 175          * explicit numeric parameter), not based on the name of the rule type. For
 176          * example, {{plural:count|wordform1|wordform2|wordform3}}, rather than
 177          * {{plural:count|one=wordform1|two=wordform2|many=wordform3}}.
 178          */
 179         private $pluralRuleTypes = null;
 180
 181         private $mergeableKeys = null;
 182
 183         /**
 184          * Constructor.
 185          * For constructor parameters, see the documentation in DefaultSettings.php
 186          * for $wgLocalisationCacheConf.
 187          *
 188          * @param array $conf
 189          * @throws MWException
 190          */
 191         function __construct( $conf ) {
 192                 global $wgCacheDirectory;
 193
 194                 $this->conf = $conf;
 195                 $storeConf = array();
 196                 if ( !empty( $conf['storeClass'] ) ) {
 197                         $storeClass = $conf['storeClass'];
 198                 } else {
 199                         switch ( $conf['store'] ) {
 200                                 case 'files':
 201                                 case 'file':
 202                                         $storeClass = 'LCStoreCDB';
 203                                         break;
 204                                 case 'db':
 205                                         $storeClass = 'LCStoreDB';
 206                                         break;
 207                                 case 'array':
 208                                         $storeClass = 'LCStoreStaticArray';
 209                                         break;
 210                                 case 'detect':
 211                                         $storeClass = $wgCacheDirectory ? 'LCStoreCDB' : 'LCStoreDB';
 212                                         break;
 213                                 default:
 214                                         throw new MWException(
 215                                                 'Please set $wgLocalisationCacheConf[\'store\'] to something sensible.' );
 216                         }
 217                 }
 218
 219                 wfDebugLog( 'caches', get_class( $this ) . ": using store $storeClass" );
 220                 if ( !empty( $conf['storeDirectory'] ) ) {
 221                         $storeConf['directory'] = $conf['storeDirectory'];
 222                 }
 223
 224                 $this->store = new $storeClass( $storeConf );
 225                 foreach ( array( 'manualRecache', 'forceRecache' ) as $var ) {
 226                         if ( isset( $conf[$var] ) ) {
 227                                 $this->$var = $conf[$var];
 228                         }
 229                 }
 230         }
 231
 232         /**
 233          * Returns true if the given key is mergeable, that is, if it is an associative
 234          * array which can be merged through a fallback sequence.
 235          * @param string $key
 236          * @return bool
 237          */
 238         public function isMergeableKey( $key ) {
 239                 if ( $this->mergeableKeys === null ) {
 240                         $this->mergeableKeys = array_flip( array_merge(
 241                                 self::$mergeableMapKeys,
 242                                 self::$mergeableListKeys,
 243                                 self::$mergeableAliasListKeys,
 244                                 self::$optionalMergeKeys,
 245                                 self::$magicWordKeys
 246                         ) );
 247                 }
 248
 249                 return isset( $this->mergeableKeys[$key] );
 250         }
 251
 252         /**
 253          * Get a cache item.
 254          *
 255          * Warning: this may be slow for split items (messages), since it will
 256          * need to fetch all of the subitems from the cache individually.
 257          * @param string $code
 258          * @param string $key
 259          * @return mixed
 260          */
 261         public function getItem( $code, $key ) {
 262                 if ( !isset( $this->loadedItems[$code][$key] ) ) {
 263                         $this->loadItem( $code, $key );
 264                 }
 265
 266                 if ( $key === 'fallback' && isset( $this->shallowFallbacks[$code] ) ) {
 267                         return $this->shallowFallbacks[$code];
 268                 }
 269
 270                 return $this->data[$code][$key];
 271         }
 272
 273         /**
 274          * Get a subitem, for instance a single message for a given language.
 275          * @param string $code
 276          * @param string $key
 277          * @param string $subkey
 278          * @return mixed|null
 279          */
 280         public function getSubitem( $code, $key, $subkey ) {
 281                 if ( !isset( $this->loadedSubitems[$code][$key][$subkey] ) &&
 282                         !isset( $this->loadedItems[$code][$key] )
 283                 ) {
 284                         $this->loadSubitem( $code, $key, $subkey );
 285                 }
 286
 287                 if ( isset( $this->data[$code][$key][$subkey] ) ) {
 288                         return $this->data[$code][$key][$subkey];
 289                 } else {
 290                         return null;
 291                 }
 292         }
 293
 294         /**
 295          * Get the list of subitem keys for a given item.
 296          *
 297          * This is faster than array_keys($lc->getItem(...)) for the items listed in
 298          * self::$splitKeys.
 299          *
 300          * Will return null if the item is not found, or false if the item is not an
 301          * array.
 302          * @param string $code
 303          * @param string $key
 304          * @return bool|null|string
 305          */
 306         public function getSubitemList( $code, $key ) {
 307                 if ( in_array( $key, self::$splitKeys ) ) {
 308                         return $this->getSubitem( $code, 'list', $key );
 309                 } else {
 310                         $item = $this->getItem( $code, $key );
 311                         if ( is_array( $item ) ) {
 312                                 return array_keys( $item );
 313                         } else {
 314                                 return false;
 315                         }
 316                 }
 317         }
 318
 319         /**
 320          * Load an item into the cache.
 321          * @param string $code
 322          * @param string $key
 323          */
 324         protected function loadItem( $code, $key ) {
 325                 if ( !isset( $this->initialisedLangs[$code] ) ) {
 326                         $this->initLanguage( $code );
 327                 }
 328
 329                 // Check to see if initLanguage() loaded it for us
 330                 if ( isset( $this->loadedItems[$code][$key] ) ) {
 331                         return;
 332                 }
 333
 334                 if ( isset( $this->shallowFallbacks[$code] ) ) {
 335                         $this->loadItem( $this->shallowFallbacks[$code], $key );
 336
 337                         return;
 338                 }
 339
 340                 if ( in_array( $key, self::$splitKeys ) ) {
 341                         $subkeyList = $this->getSubitem( $code, 'list', $key );
 342                         foreach ( $subkeyList as $subkey ) {
 343                                 if ( isset( $this->data[$code][$key][$subkey] ) ) {
 344                                         continue;
 345                                 }
 346                                 $this->data[$code][$key][$subkey] = $this->getSubitem( $code, $key, $subkey );
 347                         }
 348                 } else {
 349                         $this->data[$code][$key] = $this->store->get( $code, $key );
 350                 }
 351
 352                 $this->loadedItems[$code][$key] = true;
 353         }
 354
 355         /**
 356          * Load a subitem into the cache
 357          * @param string $code
 358          * @param string $key
 359          * @param string $subkey
 360          */
 361         protected function loadSubitem( $code, $key, $subkey ) {
 362                 if ( !in_array( $key, self::$splitKeys ) ) {
 363                         $this->loadItem( $code, $key );
 364
 365                         return;
 366                 }
 367
 368                 if ( !isset( $this->initialisedLangs[$code] ) ) {
 369                         $this->initLanguage( $code );
 370                 }
 371
 372                 // Check to see if initLanguage() loaded it for us
 373                 if ( isset( $this->loadedItems[$code][$key] ) ||
 374                         isset( $this->loadedSubitems[$code][$key][$subkey] )
 375                 ) {
 376                         return;
 377                 }
 378
 379                 if ( isset( $this->shallowFallbacks[$code] ) ) {
 380                         $this->loadSubitem( $this->shallowFallbacks[$code], $key, $subkey );
 381
 382                         return;
 383                 }
 384
 385                 $value = $this->store->get( $code, "$key:$subkey" );
 386                 $this->data[$code][$key][$subkey] = $value;
 387                 $this->loadedSubitems[$code][$key][$subkey] = true;
 388         }
 389
 390         /**
 391          * Returns true if the cache identified by $code is missing or expired.
 392          *
 393          * @param string $code
 394          *
 395          * @return bool
 396          */
 397         public function isExpired( $code ) {
 398                 if ( $this->forceRecache && !isset( $this->recachedLangs[$code] ) ) {
 399                         wfDebug( __METHOD__ . "($code): forced reload\n" );
 400
 401                         return true;
 402                 }
 403
 404                 $deps = $this->store->get( $code, 'deps' );
 405                 $keys = $this->store->get( $code, 'list' );
 406                 $preload = $this->store->get( $code, 'preload' );
 407                 // Different keys may expire separately for some stores
 408                 if ( $deps === null || $keys === null || $preload === null ) {
 409                         wfDebug( __METHOD__ . "($code): cache missing, need to make one\n" );
 410
 411                         return true;
 412                 }
 413
 414                 foreach ( $deps as $dep ) {
 415                         // Because we're unserializing stuff from cache, we
 416                         // could receive objects of classes that don't exist
 417                         // anymore (e.g. uninstalled extensions)
 418                         // When this happens, always expire the cache
 419                         if ( !$dep instanceof CacheDependency || $dep->isExpired() ) {
 420                                 wfDebug( __METHOD__ . "($code): cache for $code expired due to " .
 421                                         get_class( $dep ) . "\n" );
 422
 423                                 return true;
 424                         }
 425                 }
 426
 427                 return false;
 428         }
 429
 430         /**
 431          * Initialise a language in this object. Rebuild the cache if necessary.
 432          * @param string $code
 433          * @throws MWException
 434          */
 435         protected function initLanguage( $code ) {
 436                 if ( isset( $this->initialisedLangs[$code] ) ) {
 437                         return;
 438                 }
 439
 440                 $this->initialisedLangs[$code] = true;
 441
 442                 # If the code is of the wrong form for a Messages*.php file, do a shallow fallback
 443                 if ( !Language::isValidBuiltInCode( $code ) ) {
 444                         $this->initShallowFallback( $code, 'en' );
 445
 446                         return;
 447                 }
 448
 449                 # Recache the data if necessary
 450                 if ( !$this->manualRecache && $this->isExpired( $code ) ) {
 451                         if ( Language::isSupportedLanguage( $code ) ) {
 452                                 $this->recache( $code );
 453                         } elseif ( $code === 'en' ) {
 454                                 throw new MWException( 'MessagesEn.php is missing.' );
 455                         } else {
 456                                 $this->initShallowFallback( $code, 'en' );
 457                         }
 458
 459                         return;
 460                 }
 461
 462                 # Preload some stuff
 463                 $preload = $this->getItem( $code, 'preload' );
 464                 if ( $preload === null ) {
 465                         if ( $this->manualRecache ) {
 466                                 // No Messages*.php file. Do shallow fallback to en.
 467                                 if ( $code === 'en' ) {
 468                                         throw new MWException( 'No localisation cache found for English. ' .
 469                                                 'Please run maintenance/rebuildLocalisationCache.php.' );
 470                                 }
 471                                 $this->initShallowFallback( $code, 'en' );
 472
 473                                 return;
 474                         } else {
 475                                 throw new MWException( 'Invalid or missing localisation cache.' );
 476                         }
 477                 }
 478                 $this->data[$code] = $preload;
 479                 foreach ( $preload as $key => $item ) {
 480                         if ( in_array( $key, self::$splitKeys ) ) {
 481                                 foreach ( $item as $subkey => $subitem ) {
 482                                         $this->loadedSubitems[$code][$key][$subkey] = true;
 483                                 }
 484                         } else {
 485                                 $this->loadedItems[$code][$key] = true;
 486                         }
 487                 }
 488         }
 489
 490         /**
 491          * Create a fallback from one language to another, without creating a
 492          * complete persistent cache.
 493          * @param string $primaryCode
 494          * @param string $fallbackCode
 495          */
 496         public function initShallowFallback( $primaryCode, $fallbackCode ) {
 497                 $this->data[$primaryCode] =& $this->data[$fallbackCode];
 498                 $this->loadedItems[$primaryCode] =& $this->loadedItems[$fallbackCode];
 499                 $this->loadedSubitems[$primaryCode] =& $this->loadedSubitems[$fallbackCode];
 500                 $this->shallowFallbacks[$primaryCode] = $fallbackCode;
 501         }
 502
 503         /**
 504          * Read a PHP file containing localisation data.
 505          * @param string $_fileName
 506          * @param string $_fileType
 507          * @throws MWException
 508          * @return array
 509          */
 510         protected function readPHPFile( $_fileName, $_fileType ) {
 511                 // Disable APC caching
 512                 MediaWiki\suppressWarnings();
 513                 $_apcEnabled = ini_set( 'apc.cache_by_default', '0' );
 514                 MediaWiki\restoreWarnings();
 515
 516                 include $_fileName;
 517
 518                 MediaWiki\suppressWarnings();
 519                 ini_set( 'apc.cache_by_default', $_apcEnabled );
 520                 MediaWiki\restoreWarnings();
 521
 522                 if ( $_fileType == 'core' || $_fileType == 'extension' ) {
 523                         $data = compact( self::$allKeys );
 524                 } elseif ( $_fileType == 'aliases' ) {
 525                         $data = compact( 'aliases' );
 526                 } else {
 527                         throw new MWException( __METHOD__ . ": Invalid file type: $_fileType" );
 528                 }
 529
 530                 return $data;
 531         }
 532
 533         /**
 534          * Read a JSON file containing localisation messages.
 535          * @param string $fileName Name of file to read
 536          * @throws MWException If there is a syntax error in the JSON file
 537          * @return array Array with a 'messages' key, or empty array if the file doesn't exist
 538          */
 539         public function readJSONFile( $fileName ) {
 540
 541                 if ( !is_readable( $fileName ) ) {
 542                         return array();
 543                 }
 544
 545                 $json = file_get_contents( $fileName );
 546                 if ( $json === false ) {
 547                         return array();
 548                 }
 549
 550                 $data = FormatJson::decode( $json, true );
 551                 if ( $data === null ) {
 552
 553                         throw new MWException( __METHOD__ . ": Invalid JSON file: $fileName" );
 554                 }
 555
 556                 // Remove keys starting with '@', they're reserved for metadata and non-message data
 557                 foreach ( $data as $key => $unused ) {
 558                         if ( $key === '' || $key[0] === '@' ) {
 559                                 unset( $data[$key] );
 560                         }
 561                 }
 562
 563                 // The JSON format only supports messages, none of the other variables, so wrap the data
 564                 return array( 'messages' => $data );
 565         }
 566
 567         /**
 568          * Get the compiled plural rules for a given language from the XML files.
 569          * @since 1.20
 570          * @param string $code
 571          * @return array|null
 572          */
 573         public function getCompiledPluralRules( $code ) {
 574                 $rules = $this->getPluralRules( $code );
 575                 if ( $rules === null ) {
 576                         return null;
 577                 }
 578                 try {
 579                         $compiledRules = CLDRPluralRuleEvaluator::compile( $rules );
 580                 } catch ( CLDRPluralRuleError $e ) {
 581                         wfDebugLog( 'l10n', $e->getMessage() );
 582
 583                         return array();
 584                 }
 585
 586                 return $compiledRules;
 587         }
 588
 589         /**
 590          * Get the plural rules for a given language from the XML files.
 591          * Cached.
 592          * @since 1.20
 593          * @param string $code
 594          * @return array|null
 595          */
 596         public function getPluralRules( $code ) {
 597                 if ( $this->pluralRules === null ) {
 598                         $this->loadPluralFiles();
 599                 }
 600                 if ( !isset( $this->pluralRules[$code] ) ) {
 601                         return null;
 602                 } else {
 603                         return $this->pluralRules[$code];
 604                 }
 605         }
 606
 607         /**
 608          * Get the plural rule types for a given language from the XML files.
 609          * Cached.
 610          * @since 1.22
 611          * @param string $code
 612          * @return array|null
 613          */
 614         public function getPluralRuleTypes( $code ) {
 615                 if ( $this->pluralRuleTypes === null ) {
 616                         $this->loadPluralFiles();
 617                 }
 618                 if ( !isset( $this->pluralRuleTypes[$code] ) ) {
 619                         return null;
 620                 } else {
 621                         return $this->pluralRuleTypes[$code];
 622                 }
 623         }
 624
 625         /**
 626          * Load the plural XML files.
 627          */
 628         protected function loadPluralFiles() {
 629                 global $IP;
 630                 $cldrPlural = "$IP/languages/data/plurals.xml";
 631                 $mwPlural = "$IP/languages/data/plurals-mediawiki.xml";
 632                 // Load CLDR plural rules
 633                 $this->loadPluralFile( $cldrPlural );
 634                 if ( file_exists( $mwPlural ) ) {
 635                         // Override or extend
 636                         $this->loadPluralFile( $mwPlural );
 637                 }
 638         }
 639
 640         /**
 641          * Load a plural XML file with the given filename, compile the relevant
 642          * rules, and save the compiled rules in a process-local cache.
 643          *
 644          * @param string $fileName
 645          * @throws MWException
 646          */
 647         protected function loadPluralFile( $fileName ) {
 648                 // Use file_get_contents instead of DOMDocument::load (T58439)
 649                 $xml = file_get_contents( $fileName );
 650                 if ( !$xml ) {
 651                         throw new MWException( "Unable to read plurals file $fileName" );
 652                 }
 653                 $doc = new DOMDocument;
 654                 $doc->loadXML( $xml );
 655                 $rulesets = $doc->getElementsByTagName( "pluralRules" );
 656                 foreach ( $rulesets as $ruleset ) {
 657                         $codes = $ruleset->getAttribute( 'locales' );
 658                         $rules = array();
 659                         $ruleTypes = array();
 660                         $ruleElements = $ruleset->getElementsByTagName( "pluralRule" );
 661                         foreach ( $ruleElements as $elt ) {
 662                                 $ruleType = $elt->getAttribute( 'count' );
 663                                 if ( $ruleType === 'other' ) {
 664                                         // Don't record "other" rules, which have an empty condition
 665                                         continue;
 666                                 }
 667                                 $rules[] = $elt->nodeValue;
 668                                 $ruleTypes[] = $ruleType;
 669                         }
 670                         foreach ( explode( ' ', $codes ) as $code ) {
 671                                 $this->pluralRules[$code] = $rules;
 672                                 $this->pluralRuleTypes[$code] = $ruleTypes;
 673                         }
 674                 }
 675         }
 676
 677         /**
 678          * Read the data from the source files for a given language, and register
 679          * the relevant dependencies in the $deps array. If the localisation
 680          * exists, the data array is returned, otherwise false is returned.
 681          *
 682          * @param string $code
 683          * @param array $deps
 684          * @return array
 685          */
 686         protected function readSourceFilesAndRegisterDeps( $code, &$deps ) {
 687                 global $IP;
 688
 689                 // This reads in the PHP i18n file with non-messages l10n data
 690                 $fileName = Language::getMessagesFileName( $code );
 691                 if ( !file_exists( $fileName ) ) {
 692                         $data = array();
 693                 } else {
 694                         $deps[] = new FileDependency( $fileName );
 695                         $data = $this->readPHPFile( $fileName, 'core' );
 696                 }
 697
 698                 # Load CLDR plural rules for JavaScript
 699                 $data['pluralRules'] = $this->getPluralRules( $code );
 700                 # And for PHP
 701                 $data['compiledPluralRules'] = $this->getCompiledPluralRules( $code );
 702                 # Load plural rule types
 703                 $data['pluralRuleTypes'] = $this->getPluralRuleTypes( $code );
 704
 705                 $deps['plurals'] = new FileDependency( "$IP/languages/data/plurals.xml" );
 706                 $deps['plurals-mw'] = new FileDependency( "$IP/languages/data/plurals-mediawiki.xml" );
 707
 708                 return $data;
 709         }
 710
 711         /**
 712          * Merge two localisation values, a primary and a fallback, overwriting the
 713          * primary value in place.
 714          * @param string $key
 715          * @param mixed $value
 716          * @param mixed $fallbackValue
 717          */
 718         protected function mergeItem( $key, &$value, $fallbackValue ) {
 719                 if ( !is_null( $value ) ) {
 720                         if ( !is_null( $fallbackValue ) ) {
 721                                 if ( in_array( $key, self::$mergeableMapKeys ) ) {
 722                                         $value = $value + $fallbackValue;
 723                                 } elseif ( in_array( $key, self::$mergeableListKeys ) ) {
 724                                         $value = array_unique( array_merge( $fallbackValue, $value ) );
 725                                 } elseif ( in_array( $key, self::$mergeableAliasListKeys ) ) {
 726                                         $value = array_merge_recursive( $value, $fallbackValue );
 727                                 } elseif ( in_array( $key, self::$optionalMergeKeys ) ) {
 728                                         if ( !empty( $value['inherit'] ) ) {
 729                                                 $value = array_merge( $fallbackValue, $value );
 730                                         }
 731
 732                                         if ( isset( $value['inherit'] ) ) {
 733                                                 unset( $value['inherit'] );
 734                                         }
 735                                 } elseif ( in_array( $key, self::$magicWordKeys ) ) {
 736                                         $this->mergeMagicWords( $value, $fallbackValue );
 737                                 }
 738                         }
 739                 } else {
 740                         $value = $fallbackValue;
 741                 }
 742         }
 743
 744         /**
 745          * @param mixed $value
 746          * @param mixed $fallbackValue
 747          */
 748         protected function mergeMagicWords( &$value, $fallbackValue ) {
 749                 foreach ( $fallbackValue as $magicName => $fallbackInfo ) {
 750                         if ( !isset( $value[$magicName] ) ) {
 751                                 $value[$magicName] = $fallbackInfo;
 752                         } else {
 753                                 $oldSynonyms = array_slice( $fallbackInfo, 1 );
 754                                 $newSynonyms = array_slice( $value[$magicName], 1 );
 755                                 $synonyms = array_values( array_unique( array_merge(
 756                                         $newSynonyms, $oldSynonyms ) ) );
 757                                 $value[$magicName] = array_merge( array( $fallbackInfo[0] ), $synonyms );
 758                         }
 759                 }
 760         }
 761
 762         /**
 763          * Given an array mapping language code to localisation value, such as is
 764          * found in extension *.i18n.php files, iterate through a fallback sequence
 765          * to merge the given data with an existing primary value.
 766          *
 767          * Returns true if any data from the extension array was used, false
 768          * otherwise.
 769          * @param array $codeSequence
 770          * @param string $key
 771          * @param mixed $value
 772          * @param mixed $fallbackValue
 773          * @return bool
 774          */
 775         protected function mergeExtensionItem( $codeSequence, $key, &$value, $fallbackValue ) {
 776                 $used = false;
 777                 foreach ( $codeSequence as $code ) {
 778                         if ( isset( $fallbackValue[$code] ) ) {
 779                                 $this->mergeItem( $key, $value, $fallbackValue[$code] );
 780                                 $used = true;
 781                         }
 782                 }
 783
 784                 return $used;
 785         }
 786
 787         /**
 788          * Gets the combined list of messages dirs from
 789          * core and extensions
 790          *
 791          * @since 1.25
 792          * @return array
 793          */
 794         public function getMessagesDirs() {
 795                 global $wgMessagesDirs, $IP;
 796                 return array(
 797                         'core' => "$IP/languages/i18n",
 798                         'api' => "$IP/includes/api/i18n",
 799                         'oojs-ui' => "$IP/resources/lib/oojs-ui/i18n",
 800                 ) + $wgMessagesDirs;
 801         }
 802
 803         /**
 804          * Load localisation data for a given language for both core and extensions
 805          * and save it to the persistent cache store and the process cache
 806          * @param string $code
 807          * @throws MWException
 808          */
 809         public function recache( $code ) {
 810                 global $wgExtensionMessagesFiles;
 811
 812                 if ( !$code ) {
 813                         throw new MWException( "Invalid language code requested" );
 814                 }
 815                 $this->recachedLangs[$code] = true;
 816
 817                 # Initial values
 818                 $initialData = array_combine(
 819                         self::$allKeys,
 820                         array_fill( 0, count( self::$allKeys ), null ) );
 821                 $coreData = $initialData;
 822                 $deps = array();
 823
 824                 # Load the primary localisation from the source file
 825                 $data = $this->readSourceFilesAndRegisterDeps( $code, $deps );
 826                 if ( $data === false ) {
 827                         wfDebug( __METHOD__ . ": no localisation file for $code, using fallback to en\n" );
 828                         $coreData['fallback'] = 'en';
 829                 } else {
 830                         wfDebug( __METHOD__ . ": got localisation for $code from source\n" );
 831
 832                         # Merge primary localisation
 833                         foreach ( $data as $key => $value ) {
 834                                 $this->mergeItem( $key, $coreData[$key], $value );
 835                         }
 836                 }
 837
 838                 # Fill in the fallback if it's not there already
 839                 if ( is_null( $coreData['fallback'] ) ) {
 840                         $coreData['fallback'] = $code === 'en' ? false : 'en';
 841                 }
 842                 if ( $coreData['fallback'] === false ) {
 843                         $coreData['fallbackSequence'] = array();
 844                 } else {
 845                         $coreData['fallbackSequence'] = array_map( 'trim', explode( ',', $coreData['fallback'] ) );
 846                         $len = count( $coreData['fallbackSequence'] );
 847
 848                         # Ensure that the sequence ends at en
 849                         if ( $coreData['fallbackSequence'][$len - 1] !== 'en' ) {
 850                                 $coreData['fallbackSequence'][] = 'en';
 851                         }
 852                 }
 853
 854                 $codeSequence = array_merge( array( $code ), $coreData['fallbackSequence'] );
 855                 $messageDirs = $this->getMessagesDirs();
 856
 857                 # Load non-JSON localisation data for extensions
 858                 $extensionData = array_combine(
 859                         $codeSequence,
 860                         array_fill( 0, count( $codeSequence ), $initialData ) );
 861                 foreach ( $wgExtensionMessagesFiles as $extension => $fileName ) {
 862                         if ( isset( $messageDirs[$extension] ) ) {
 863                                 # This extension has JSON message data; skip the PHP shim
 864                                 continue;
 865                         }
 866
 867                         $data = $this->readPHPFile( $fileName, 'extension' );
 868                         $used = false;
 869
 870                         foreach ( $data as $key => $item ) {
 871                                 foreach ( $codeSequence as $csCode ) {
 872                                         if ( isset( $item[$csCode] ) ) {
 873                                                 $this->mergeItem( $key, $extensionData[$csCode][$key], $item[$csCode] );
 874                                                 $used = true;
 875                                         }
 876                                 }
 877                         }
 878
 879                         if ( $used ) {
 880                                 $deps[] = new FileDependency( $fileName );
 881                         }
 882                 }
 883
 884                 # Load the localisation data for each fallback, then merge it into the full array
 885                 $allData = $initialData;
 886                 foreach ( $codeSequence as $csCode ) {
 887                         $csData = $initialData;
 888
 889                         # Load core messages and the extension localisations.
 890                         foreach ( $messageDirs as $dirs ) {
 891                                 foreach ( (array)$dirs as $dir ) {
 892                                         $fileName = "$dir/$csCode.json";
 893                                         $data = $this->readJSONFile( $fileName );
 894
 895                                         foreach ( $data as $key => $item ) {
 896                                                 $this->mergeItem( $key, $csData[$key], $item );
 897                                         }
 898
 899                                         $deps[] = new FileDependency( $fileName );
 900                                 }
 901                         }
 902
 903                         # Merge non-JSON extension data
 904                         if ( isset( $extensionData[$csCode] ) ) {
 905                                 foreach ( $extensionData[$csCode] as $key => $item ) {
 906                                         $this->mergeItem( $key, $csData[$key], $item );
 907                                 }
 908                         }
 909
 910                         if ( $csCode === $code ) {
 911                                 # Merge core data into extension data
 912                                 foreach ( $coreData as $key => $item ) {
 913                                         $this->mergeItem( $key, $csData[$key], $item );
 914                                 }
 915                         } else {
 916                                 # Load the secondary localisation from the source file to
 917                                 # avoid infinite cycles on cyclic fallbacks
 918                                 $fbData = $this->readSourceFilesAndRegisterDeps( $csCode, $deps );
 919                                 if ( $fbData !== false ) {
 920                                         # Only merge the keys that make sense to merge
 921                                         foreach ( self::$allKeys as $key ) {
 922                                                 if ( !isset( $fbData[$key] ) ) {
 923                                                         continue;
 924                                                 }
 925
 926                                                 if ( is_null( $coreData[$key] ) || $this->isMergeableKey( $key ) ) {
 927                                                         $this->mergeItem( $key, $csData[$key], $fbData[$key] );
 928                                                 }
 929                                         }
 930                                 }
 931                         }
 932
 933                         # Allow extensions an opportunity to adjust the data for this
 934                         # fallback
 935                         Hooks::run( 'LocalisationCacheRecacheFallback', array( $this, $csCode, &$csData ) );
 936
 937                         # Merge the data for this fallback into the final array
 938                         if ( $csCode === $code ) {
 939                                 $allData = $csData;
 940                         } else {
 941                                 foreach ( self::$allKeys as $key ) {
 942                                         if ( !isset( $csData[$key] ) ) {
 943                                                 continue;
 944                                         }
 945
 946                                         if ( is_null( $allData[$key] ) || $this->isMergeableKey( $key ) ) {
 947                                                 $this->mergeItem( $key, $allData[$key], $csData[$key] );
 948                                         }
 949                                 }
 950                         }
 951                 }
 952
 953                 # Add cache dependencies for any referenced globals
 954                 $deps['wgExtensionMessagesFiles'] = new GlobalDependency( 'wgExtensionMessagesFiles' );
 955                 // $wgMessagesDirs is used in LocalisationCache::getMessagesDirs()
 956                 $deps['wgMessagesDirs'] = new GlobalDependency( 'wgMessagesDirs' );
 957                 $deps['version'] = new ConstantDependency( 'LocalisationCache::VERSION' );
 958
 959                 # Add dependencies to the cache entry
 960                 $allData['deps'] = $deps;
 961
 962                 # Replace spaces with underscores in namespace names
 963                 $allData['namespaceNames'] = str_replace( ' ', '_', $allData['namespaceNames'] );
 964
 965                 # And do the same for special page aliases. $page is an array.
 966                 foreach ( $allData['specialPageAliases'] as &$page ) {
 967                         $page = str_replace( ' ', '_', $page );
 968                 }
 969                 # Decouple the reference to prevent accidental damage
 970                 unset( $page );
 971
 972                 # If there were no plural rules, return an empty array
 973                 if ( $allData['pluralRules'] === null ) {
 974                         $allData['pluralRules'] = array();
 975                 }
 976                 if ( $allData['compiledPluralRules'] === null ) {
 977                         $allData['compiledPluralRules'] = array();
 978                 }
 979                 # If there were no plural rule types, return an empty array
 980                 if ( $allData['pluralRuleTypes'] === null ) {
 981                         $allData['pluralRuleTypes'] = array();
 982                 }
 983
 984                 # Set the list keys
 985                 $allData['list'] = array();
 986                 foreach ( self::$splitKeys as $key ) {
 987                         $allData['list'][$key] = array_keys( $allData[$key] );
 988                 }
 989                 # Run hooks
 990                 $purgeBlobs = true;
 991                 Hooks::run( 'LocalisationCacheRecache', array( $this, $code, &$allData, &$purgeBlobs ) );
 992
 993                 if ( is_null( $allData['namespaceNames'] ) ) {
 994                         throw new MWException( __METHOD__ . ': Localisation data failed sanity check! ' .
 995                                 'Check that your languages/messages/MessagesEn.php file is intact.' );
 996                 }
 997
 998                 # Set the preload key
 999                 $allData['preload'] = $this->buildPreload( $allData );
1000
1001                 # Save to the process cache and register the items loaded
1002                 $this->data[$code] = $allData;
1003                 foreach ( $allData as $key => $item ) {
1004                         $this->loadedItems[$code][$key] = true;
1005                 }
1006
1007                 # Save to the persistent cache
1008                 $this->store->startWrite( $code );
1009                 foreach ( $allData as $key => $value ) {
1010                         if ( in_array( $key, self::$splitKeys ) ) {
1011                                 foreach ( $value as $subkey => $subvalue ) {
1012                                         $this->store->set( "$key:$subkey", $subvalue );
1013                                 }
1014                         } else {
1015                                 $this->store->set( $key, $value );
1016                         }
1017                 }
1018                 $this->store->finishWrite();
1019
1020                 # Clear out the MessageBlobStore
1021                 # HACK: If using a null (i.e. disabled) storage backend, we
1022                 # can't write to the MessageBlobStore either
1023                 if ( $purgeBlobs && !$this->store instanceof LCStoreNull ) {
1024                         $blobStore = new MessageBlobStore();
1025                         $blobStore->clear();
1026                 }
1027
1028         }
1029
1030         /**
1031          * Build the preload item from the given pre-cache data.
1032          *
1033          * The preload item will be loaded automatically, improving performance
1034          * for the commonly-requested items it contains.
1035          * @param array $data
1036          * @return array
1037          */
1038         protected function buildPreload( $data ) {
1039                 $preload = array( 'messages' => array() );
1040                 foreach ( self::$preloadedKeys as $key ) {
1041                         $preload[$key] = $data[$key];
1042                 }
1043
1044                 foreach ( $data['preloadedMessages'] as $subkey ) {
1045                         if ( isset( $data['messages'][$subkey] ) ) {
1046                                 $subitem = $data['messages'][$subkey];
1047                         } else {
1048                                 $subitem = null;
1049                         }
1050                         $preload['messages'][$subkey] = $subitem;
1051                 }
1052
1053                 return $preload;
1054         }
1055
1056         /**
1057          * Unload the data for a given language from the object cache.
1058          * Reduces memory usage.
1059          * @param string $code
1060          */
1061         public function unload( $code ) {
1062                 unset( $this->data[$code] );
1063                 unset( $this->loadedItems[$code] );
1064                 unset( $this->loadedSubitems[$code] );
1065                 unset( $this->initialisedLangs[$code] );
1066                 unset( $this->shallowFallbacks[$code] );
1067
1068                 foreach ( $this->shallowFallbacks as $shallowCode => $fbCode ) {
1069                         if ( $fbCode === $code ) {
1070                                 $this->unload( $shallowCode );
1071                         }
1072                 }
1073         }
1074
1075         /**
1076          * Unload all data
1077          */
1078         public function unloadAll() {
1079                 foreach ( $this->initialisedLangs as $lang => $unused ) {
1080                         $this->unload( $lang );
1081                 }
1082         }
1083
1084         /**
1085          * Disable the storage backend
1086          */
1087         public function disableBackend() {
1088                 $this->store = new LCStoreNull;
1089                 $this->manualRecache = false;
1090         }
1091 }
1092
1093 /**
1094  * Interface for the persistence layer of LocalisationCache.
1095  *
1096  * The persistence layer is two-level hierarchical cache. The first level
1097  * is the language, the second level is the item or subitem.
1098  *
1099  * Since the data for a whole language is rebuilt in one operation, it needs
1100  * to have a fast and atomic method for deleting or replacing all of the
1101  * current data for a given language. The interface reflects this bulk update
1102  * operation. Callers writing to the cache must first call startWrite(), then
1103  * will call set() a couple of thousand times, then will call finishWrite()
1104  * to commit the operation. When finishWrite() is called, the cache is
1105  * expected to delete all data previously stored for that language.
1106  *
1107  * The values stored are PHP variables suitable for serialize(). Implementations
1108  * of LCStore are responsible for serializing and unserializing.
1109  */
1110 interface LCStore {
1111         /**
1112          * Get a value.
1113          * @param string $code Language code
1114          * @param string $key Cache key
1115          */
1116         function get( $code, $key );
1117
1118         /**
1119          * Start a write transaction.
1120          * @param string $code Language code
1121          */
1122         function startWrite( $code );
1123
1124         /**
1125          * Finish a write transaction.
1126          */
1127         function finishWrite();
1128
1129         /**
1130          * Set a key to a given value. startWrite() must be called before this
1131          * is called, and finishWrite() must be called afterwards.
1132          * @param string $key
1133          * @param mixed $value
1134          */
1135         function set( $key, $value );
1136 }
1137
1138 /**
1139  * LCStore implementation which uses the standard DB functions to store data.
1140  * This will work on any MediaWiki installation.
1141  */
1142 class LCStoreDB implements LCStore {
1143         private $currentLang;
1144         private $writesDone = false;
1145
1146         /** @var DatabaseBase */
1147         private $dbw;
1148         /** @var array */
1149         private $batch = array();
1150
1151         private $readOnly = false;
1152
1153         public function get( $code, $key ) {
1154                 if ( $this->writesDone ) {
1155                         $db = wfGetDB( DB_MASTER );
1156                 } else {
1157                         $db = wfGetDB( DB_SLAVE );
1158                 }
1159                 $row = $db->selectRow( 'l10n_cache', array( 'lc_value' ),
1160                         array( 'lc_lang' => $code, 'lc_key' => $key ), __METHOD__ );
1161                 if ( $row ) {
1162                         return unserialize( $db->decodeBlob( $row->lc_value ) );
1163                 } else {
1164                         return null;
1165                 }
1166         }
1167
1168         public function startWrite( $code ) {
1169                 if ( $this->readOnly ) {
1170                         return;
1171                 } elseif ( !$code ) {
1172                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
1173                 }
1174
1175                 $this->dbw = wfGetDB( DB_MASTER );
1176
1177                 $this->currentLang = $code;
1178                 $this->batch = array();
1179         }
1180
1181         public function finishWrite() {
1182                 if ( $this->readOnly ) {
1183                         return;
1184                 } elseif ( is_null( $this->currentLang ) ) {
1185                         throw new MWException( __CLASS__ . ': must call startWrite() before finishWrite()' );
1186                 }
1187
1188                 $this->dbw->begin( __METHOD__ );
1189                 try {
1190                         $this->dbw->delete( 'l10n_cache',
1191                                 array( 'lc_lang' => $this->currentLang ), __METHOD__ );
1192                         foreach ( array_chunk( $this->batch, 500 ) as $rows ) {
1193                                 $this->dbw->insert( 'l10n_cache', $rows, __METHOD__ );
1194                         }
1195                         $this->writesDone = true;
1196                 } catch ( DBQueryError $e ) {
1197                         if ( $this->dbw->wasReadOnlyError() ) {
1198                                 $this->readOnly = true; // just avoid site down time
1199                         } else {
1200                                 throw $e;
1201                         }
1202                 }
1203                 $this->dbw->commit( __METHOD__ );
1204
1205                 $this->currentLang = null;
1206                 $this->batch = array();
1207         }
1208
1209         public function set( $key, $value ) {
1210                 if ( $this->readOnly ) {
1211                         return;
1212                 } elseif ( is_null( $this->currentLang ) ) {
1213                         throw new MWException( __CLASS__ . ': must call startWrite() before set()' );
1214                 }
1215
1216                 $this->batch[] = array(
1217                         'lc_lang' => $this->currentLang,
1218                         'lc_key' => $key,
1219                         'lc_value' => $this->dbw->encodeBlob( serialize( $value ) ) );
1220         }
1221 }
1222
1223 /**
1224  * LCStore implementation which stores data as a collection of CDB files in the
1225  * directory given by $wgCacheDirectory. If $wgCacheDirectory is not set, this
1226  * will throw an exception.
1227  *
1228  * Profiling indicates that on Linux, this implementation outperforms MySQL if
1229  * the directory is on a local filesystem and there is ample kernel cache
1230  * space. The performance advantage is greater when the DBA extension is
1231  * available than it is with the PHP port.
1232  *
1233  * See Cdb.php and http://cr.yp.to/cdb.html
1234  */
1235 class LCStoreCDB implements LCStore {
1236         /** @var CdbReader[] */
1237         private $readers;
1238
1239         /** @var CdbWriter */
1240         private $writer;
1241
1242         /** @var string Current language code */
1243         private $currentLang;
1244
1245         /** @var bool|string Cache directory. False if not set */
1246         private $directory;
1247
1248         function __construct( $conf = array() ) {
1249                 global $wgCacheDirectory;
1250
1251                 if ( isset( $conf['directory'] ) ) {
1252                         $this->directory = $conf['directory'];
1253                 } else {
1254                         $this->directory = $wgCacheDirectory;
1255                 }
1256         }
1257
1258         public function get( $code, $key ) {
1259                 if ( !isset( $this->readers[$code] ) ) {
1260                         $fileName = $this->getFileName( $code );
1261
1262                         $this->readers[$code] = false;
1263                         if ( file_exists( $fileName ) ) {
1264                                 try {
1265                                         $this->readers[$code] = CdbReader::open( $fileName );
1266                                 } catch ( CdbException $e ) {
1267                                         wfDebug( __METHOD__ . ": unable to open cdb file for reading\n" );
1268                                 }
1269                         }
1270                 }
1271
1272                 if ( !$this->readers[$code] ) {
1273                         return null;
1274                 } else {
1275                         $value = false;
1276                         try {
1277                                 $value = $this->readers[$code]->get( $key );
1278                         } catch ( CdbException $e ) {
1279                                 wfDebug( __METHOD__ . ": CdbException caught, error message was "
1280                                         . $e->getMessage() . "\n" );
1281                         }
1282                         if ( $value === false ) {
1283                                 return null;
1284                         }
1285
1286                         return unserialize( $value );
1287                 }
1288         }
1289
1290         public function startWrite( $code ) {
1291                 if ( !file_exists( $this->directory ) ) {
1292                         if ( !wfMkdirParents( $this->directory, null, __METHOD__ ) ) {
1293                                 throw new MWException( "Unable to create the localisation store " .
1294                                         "directory \"{$this->directory}\"" );
1295                         }
1296                 }
1297
1298                 // Close reader to stop permission errors on write
1299                 if ( !empty( $this->readers[$code] ) ) {
1300                         $this->readers[$code]->close();
1301                 }
1302
1303                 try {
1304                         $this->writer = CdbWriter::open( $this->getFileName( $code ) );
1305                 } catch ( CdbException $e ) {
1306                         throw new MWException( $e->getMessage() );
1307                 }
1308                 $this->currentLang = $code;
1309         }
1310
1311         public function finishWrite() {
1312                 // Close the writer
1313                 try {
1314                         $this->writer->close();
1315                 } catch ( CdbException $e ) {
1316                         throw new MWException( $e->getMessage() );
1317                 }
1318                 $this->writer = null;
1319                 unset( $this->readers[$this->currentLang] );
1320                 $this->currentLang = null;
1321         }
1322
1323         public function set( $key, $value ) {
1324                 if ( is_null( $this->writer ) ) {
1325                         throw new MWException( __CLASS__ . ': must call startWrite() before calling set()' );
1326                 }
1327                 try {
1328                         $this->writer->set( $key, serialize( $value ) );
1329                 } catch ( CdbException $e ) {
1330                         throw new MWException( $e->getMessage() );
1331                 }
1332         }
1333
1334         protected function getFileName( $code ) {
1335                 if ( strval( $code ) === '' || strpos( $code, '/' ) !== false ) {
1336                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
1337                 }
1338
1339                 return "{$this->directory}/l10n_cache-$code.cdb";
1340         }
1341 }
1342
1343 /**
1344  * Null store backend, used to avoid DB errors during install
1345  */
1346 class LCStoreNull implements LCStore {
1347         public function get( $code, $key ) {
1348                 return null;
1349         }
1350
1351         public function startWrite( $code ) {
1352         }
1353
1354         public function finishWrite() {
1355         }
1356
1357         public function set( $key, $value ) {
1358         }
1359 }
1360
1361 /**
1362  * A localisation cache optimised for loading large amounts of data for many
1363  * languages. Used by rebuildLocalisationCache.php.
1364  */
1365 class LocalisationCacheBulkLoad extends LocalisationCache {
1366         /**
1367          * A cache of the contents of data files.
1368          * Core files are serialized to avoid using ~1GB of RAM during a recache.
1369          */
1370         private $fileCache = array();
1371
1372         /**
1373          * Most recently used languages. Uses the linked-list aspect of PHP hashtables
1374          * to keep the most recently used language codes at the end of the array, and
1375          * the language codes that are ready to be deleted at the beginning.
1376          */
1377         private $mruLangs = array();
1378
1379         /**
1380          * Maximum number of languages that may be loaded into $this->data
1381          */
1382         private $maxLoadedLangs = 10;
1383
1384         /**
1385          * @param string $fileName
1386          * @param string $fileType
1387          * @return array|mixed
1388          */
1389         protected function readPHPFile( $fileName, $fileType ) {
1390                 $serialize = $fileType === 'core';
1391                 if ( !isset( $this->fileCache[$fileName][$fileType] ) ) {
1392                         $data = parent::readPHPFile( $fileName, $fileType );
1393
1394                         if ( $serialize ) {
1395                                 $encData = serialize( $data );
1396                         } else {
1397                                 $encData = $data;
1398                         }
1399
1400                         $this->fileCache[$fileName][$fileType] = $encData;
1401
1402                         return $data;
1403                 } elseif ( $serialize ) {
1404                         return unserialize( $this->fileCache[$fileName][$fileType] );
1405                 } else {
1406                         return $this->fileCache[$fileName][$fileType];
1407                 }
1408         }
1409
1410         /**
1411          * @param string $code
1412          * @param string $key
1413          * @return mixed
1414          */
1415         public function getItem( $code, $key ) {
1416                 unset( $this->mruLangs[$code] );
1417                 $this->mruLangs[$code] = true;
1418
1419                 return parent::getItem( $code, $key );
1420         }
1421
1422         /**
1423          * @param string $code
1424          * @param string $key
1425          * @param string $subkey
1426          * @return mixed
1427          */
1428         public function getSubitem( $code, $key, $subkey ) {
1429                 unset( $this->mruLangs[$code] );
1430                 $this->mruLangs[$code] = true;
1431
1432                 return parent::getSubitem( $code, $key, $subkey );
1433         }
1434
1435         /**
1436          * @param string $code
1437          */
1438         public function recache( $code ) {
1439                 parent::recache( $code );
1440                 unset( $this->mruLangs[$code] );
1441                 $this->mruLangs[$code] = true;
1442                 $this->trimCache();
1443         }
1444
1445         /**
1446          * @param string $code
1447          */
1448         public function unload( $code ) {
1449                 unset( $this->mruLangs[$code] );
1450                 parent::unload( $code );
1451         }
1452
1453         /**
1454          * Unload cached languages until there are less than $this->maxLoadedLangs
1455          */
1456         protected function trimCache() {
1457                 while ( count( $this->data ) > $this->maxLoadedLangs && count( $this->mruLangs ) ) {
1458                         reset( $this->mruLangs );
1459                         $code = key( $this->mruLangs );
1460                         wfDebug( __METHOD__ . ": unloading $code\n" );
1461                         $this->unload( $code );
1462                 }
1463         }
1464 }