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
 543                         return array();
 544                 }
 545
 546                 $json = file_get_contents( $fileName );
 547                 if ( $json === false ) {
 548
 549                         return array();
 550                 }
 551
 552                 $data = FormatJson::decode( $json, true );
 553                 if ( $data === null ) {
 554
 555                         throw new MWException( __METHOD__ . ": Invalid JSON file: $fileName" );
 556                 }
 557
 558                 // Remove keys starting with '@', they're reserved for metadata and non-message data
 559                 foreach ( $data as $key => $unused ) {
 560                         if ( $key === '' || $key[0] === '@' ) {
 561                                 unset( $data[$key] );
 562                         }
 563                 }
 564
 565                 // The JSON format only supports messages, none of the other variables, so wrap the data
 566                 return array( 'messages' => $data );
 567         }
 568
 569         /**
 570          * Get the compiled plural rules for a given language from the XML files.
 571          * @since 1.20
 572          * @param string $code
 573          * @return array|null
 574          */
 575         public function getCompiledPluralRules( $code ) {
 576                 $rules = $this->getPluralRules( $code );
 577                 if ( $rules === null ) {
 578                         return null;
 579                 }
 580                 try {
 581                         $compiledRules = CLDRPluralRuleEvaluator::compile( $rules );
 582                 } catch ( CLDRPluralRuleError $e ) {
 583                         wfDebugLog( 'l10n', $e->getMessage() );
 584
 585                         return array();
 586                 }
 587
 588                 return $compiledRules;
 589         }
 590
 591         /**
 592          * Get the plural rules for a given language from the XML files.
 593          * Cached.
 594          * @since 1.20
 595          * @param string $code
 596          * @return array|null
 597          */
 598         public function getPluralRules( $code ) {
 599                 if ( $this->pluralRules === null ) {
 600                         $this->loadPluralFiles();
 601                 }
 602                 if ( !isset( $this->pluralRules[$code] ) ) {
 603                         return null;
 604                 } else {
 605                         return $this->pluralRules[$code];
 606                 }
 607         }
 608
 609         /**
 610          * Get the plural rule types for a given language from the XML files.
 611          * Cached.
 612          * @since 1.22
 613          * @param string $code
 614          * @return array|null
 615          */
 616         public function getPluralRuleTypes( $code ) {
 617                 if ( $this->pluralRuleTypes === null ) {
 618                         $this->loadPluralFiles();
 619                 }
 620                 if ( !isset( $this->pluralRuleTypes[$code] ) ) {
 621                         return null;
 622                 } else {
 623                         return $this->pluralRuleTypes[$code];
 624                 }
 625         }
 626
 627         /**
 628          * Load the plural XML files.
 629          */
 630         protected function loadPluralFiles() {
 631                 global $IP;
 632                 $cldrPlural = "$IP/languages/data/plurals.xml";
 633                 $mwPlural = "$IP/languages/data/plurals-mediawiki.xml";
 634                 // Load CLDR plural rules
 635                 $this->loadPluralFile( $cldrPlural );
 636                 if ( file_exists( $mwPlural ) ) {
 637                         // Override or extend
 638                         $this->loadPluralFile( $mwPlural );
 639                 }
 640         }
 641
 642         /**
 643          * Load a plural XML file with the given filename, compile the relevant
 644          * rules, and save the compiled rules in a process-local cache.
 645          *
 646          * @param string $fileName
 647          * @throws MWException
 648          */
 649         protected function loadPluralFile( $fileName ) {
 650                 // Use file_get_contents instead of DOMDocument::load (T58439)
 651                 $xml = file_get_contents( $fileName );
 652                 if ( !$xml ) {
 653                         throw new MWException( "Unable to read plurals file $fileName" );
 654                 }
 655                 $doc = new DOMDocument;
 656                 $doc->loadXML( $xml );
 657                 $rulesets = $doc->getElementsByTagName( "pluralRules" );
 658                 foreach ( $rulesets as $ruleset ) {
 659                         $codes = $ruleset->getAttribute( 'locales' );
 660                         $rules = array();
 661                         $ruleTypes = array();
 662                         $ruleElements = $ruleset->getElementsByTagName( "pluralRule" );
 663                         foreach ( $ruleElements as $elt ) {
 664                                 $ruleType = $elt->getAttribute( 'count' );
 665                                 if ( $ruleType === 'other' ) {
 666                                         // Don't record "other" rules, which have an empty condition
 667                                         continue;
 668                                 }
 669                                 $rules[] = $elt->nodeValue;
 670                                 $ruleTypes[] = $ruleType;
 671                         }
 672                         foreach ( explode( ' ', $codes ) as $code ) {
 673                                 $this->pluralRules[$code] = $rules;
 674                                 $this->pluralRuleTypes[$code] = $ruleTypes;
 675                         }
 676                 }
 677         }
 678
 679         /**
 680          * Read the data from the source files for a given language, and register
 681          * the relevant dependencies in the $deps array. If the localisation
 682          * exists, the data array is returned, otherwise false is returned.
 683          *
 684          * @param string $code
 685          * @param array $deps
 686          * @return array
 687          */
 688         protected function readSourceFilesAndRegisterDeps( $code, &$deps ) {
 689                 global $IP;
 690
 691                 // This reads in the PHP i18n file with non-messages l10n data
 692                 $fileName = Language::getMessagesFileName( $code );
 693                 if ( !file_exists( $fileName ) ) {
 694                         $data = array();
 695                 } else {
 696                         $deps[] = new FileDependency( $fileName );
 697                         $data = $this->readPHPFile( $fileName, 'core' );
 698                 }
 699
 700                 # Load CLDR plural rules for JavaScript
 701                 $data['pluralRules'] = $this->getPluralRules( $code );
 702                 # And for PHP
 703                 $data['compiledPluralRules'] = $this->getCompiledPluralRules( $code );
 704                 # Load plural rule types
 705                 $data['pluralRuleTypes'] = $this->getPluralRuleTypes( $code );
 706
 707                 $deps['plurals'] = new FileDependency( "$IP/languages/data/plurals.xml" );
 708                 $deps['plurals-mw'] = new FileDependency( "$IP/languages/data/plurals-mediawiki.xml" );
 709
 710                 return $data;
 711         }
 712
 713         /**
 714          * Merge two localisation values, a primary and a fallback, overwriting the
 715          * primary value in place.
 716          * @param string $key
 717          * @param mixed $value
 718          * @param mixed $fallbackValue
 719          */
 720         protected function mergeItem( $key, &$value, $fallbackValue ) {
 721                 if ( !is_null( $value ) ) {
 722                         if ( !is_null( $fallbackValue ) ) {
 723                                 if ( in_array( $key, self::$mergeableMapKeys ) ) {
 724                                         $value = $value + $fallbackValue;
 725                                 } elseif ( in_array( $key, self::$mergeableListKeys ) ) {
 726                                         $value = array_unique( array_merge( $fallbackValue, $value ) );
 727                                 } elseif ( in_array( $key, self::$mergeableAliasListKeys ) ) {
 728                                         $value = array_merge_recursive( $value, $fallbackValue );
 729                                 } elseif ( in_array( $key, self::$optionalMergeKeys ) ) {
 730                                         if ( !empty( $value['inherit'] ) ) {
 731                                                 $value = array_merge( $fallbackValue, $value );
 732                                         }
 733
 734                                         if ( isset( $value['inherit'] ) ) {
 735                                                 unset( $value['inherit'] );
 736                                         }
 737                                 } elseif ( in_array( $key, self::$magicWordKeys ) ) {
 738                                         $this->mergeMagicWords( $value, $fallbackValue );
 739                                 }
 740                         }
 741                 } else {
 742                         $value = $fallbackValue;
 743                 }
 744         }
 745
 746         /**
 747          * @param mixed $value
 748          * @param mixed $fallbackValue
 749          */
 750         protected function mergeMagicWords( &$value, $fallbackValue ) {
 751                 foreach ( $fallbackValue as $magicName => $fallbackInfo ) {
 752                         if ( !isset( $value[$magicName] ) ) {
 753                                 $value[$magicName] = $fallbackInfo;
 754                         } else {
 755                                 $oldSynonyms = array_slice( $fallbackInfo, 1 );
 756                                 $newSynonyms = array_slice( $value[$magicName], 1 );
 757                                 $synonyms = array_values( array_unique( array_merge(
 758                                         $newSynonyms, $oldSynonyms ) ) );
 759                                 $value[$magicName] = array_merge( array( $fallbackInfo[0] ), $synonyms );
 760                         }
 761                 }
 762         }
 763
 764         /**
 765          * Given an array mapping language code to localisation value, such as is
 766          * found in extension *.i18n.php files, iterate through a fallback sequence
 767          * to merge the given data with an existing primary value.
 768          *
 769          * Returns true if any data from the extension array was used, false
 770          * otherwise.
 771          * @param array $codeSequence
 772          * @param string $key
 773          * @param mixed $value
 774          * @param mixed $fallbackValue
 775          * @return bool
 776          */
 777         protected function mergeExtensionItem( $codeSequence, $key, &$value, $fallbackValue ) {
 778                 $used = false;
 779                 foreach ( $codeSequence as $code ) {
 780                         if ( isset( $fallbackValue[$code] ) ) {
 781                                 $this->mergeItem( $key, $value, $fallbackValue[$code] );
 782                                 $used = true;
 783                         }
 784                 }
 785
 786                 return $used;
 787         }
 788
 789         /**
 790          * Gets the combined list of messages dirs from
 791          * core and extensions
 792          *
 793          * @since 1.25
 794          * @return array
 795          */
 796         public function getMessagesDirs() {
 797                 global $wgMessagesDirs, $IP;
 798                 return array(
 799                         'core' => "$IP/languages/i18n",
 800                         'api' => "$IP/includes/api/i18n",
 801                         'oojs-ui' => "$IP/resources/lib/oojs-ui/i18n",
 802                 ) + $wgMessagesDirs;
 803         }
 804
 805         /**
 806          * Load localisation data for a given language for both core and extensions
 807          * and save it to the persistent cache store and the process cache
 808          * @param string $code
 809          * @throws MWException
 810          */
 811         public function recache( $code ) {
 812                 global $wgExtensionMessagesFiles;
 813
 814                 if ( !$code ) {
 815                         throw new MWException( "Invalid language code requested" );
 816                 }
 817                 $this->recachedLangs[$code] = true;
 818
 819                 # Initial values
 820                 $initialData = array_combine(
 821                         self::$allKeys,
 822                         array_fill( 0, count( self::$allKeys ), null ) );
 823                 $coreData = $initialData;
 824                 $deps = array();
 825
 826                 # Load the primary localisation from the source file
 827                 $data = $this->readSourceFilesAndRegisterDeps( $code, $deps );
 828                 if ( $data === false ) {
 829                         wfDebug( __METHOD__ . ": no localisation file for $code, using fallback to en\n" );
 830                         $coreData['fallback'] = 'en';
 831                 } else {
 832                         wfDebug( __METHOD__ . ": got localisation for $code from source\n" );
 833
 834                         # Merge primary localisation
 835                         foreach ( $data as $key => $value ) {
 836                                 $this->mergeItem( $key, $coreData[$key], $value );
 837                         }
 838                 }
 839
 840                 # Fill in the fallback if it's not there already
 841                 if ( is_null( $coreData['fallback'] ) ) {
 842                         $coreData['fallback'] = $code === 'en' ? false : 'en';
 843                 }
 844                 if ( $coreData['fallback'] === false ) {
 845                         $coreData['fallbackSequence'] = array();
 846                 } else {
 847                         $coreData['fallbackSequence'] = array_map( 'trim', explode( ',', $coreData['fallback'] ) );
 848                         $len = count( $coreData['fallbackSequence'] );
 849
 850                         # Ensure that the sequence ends at en
 851                         if ( $coreData['fallbackSequence'][$len - 1] !== 'en' ) {
 852                                 $coreData['fallbackSequence'][] = 'en';
 853                         }
 854                 }
 855
 856                 $codeSequence = array_merge( array( $code ), $coreData['fallbackSequence'] );
 857                 $messageDirs = $this->getMessagesDirs();
 858
 859                 # Load non-JSON localisation data for extensions
 860                 $extensionData = array_combine(
 861                         $codeSequence,
 862                         array_fill( 0, count( $codeSequence ), $initialData ) );
 863                 foreach ( $wgExtensionMessagesFiles as $extension => $fileName ) {
 864                         if ( isset( $messageDirs[$extension] ) ) {
 865                                 # This extension has JSON message data; skip the PHP shim
 866                                 continue;
 867                         }
 868
 869                         $data = $this->readPHPFile( $fileName, 'extension' );
 870                         $used = false;
 871
 872                         foreach ( $data as $key => $item ) {
 873                                 foreach ( $codeSequence as $csCode ) {
 874                                         if ( isset( $item[$csCode] ) ) {
 875                                                 $this->mergeItem( $key, $extensionData[$csCode][$key], $item[$csCode] );
 876                                                 $used = true;
 877                                         }
 878                                 }
 879                         }
 880
 881                         if ( $used ) {
 882                                 $deps[] = new FileDependency( $fileName );
 883                         }
 884                 }
 885
 886                 # Load the localisation data for each fallback, then merge it into the full array
 887                 $allData = $initialData;
 888                 foreach ( $codeSequence as $csCode ) {
 889                         $csData = $initialData;
 890
 891                         # Load core messages and the extension localisations.
 892                         foreach ( $messageDirs as $dirs ) {
 893                                 foreach ( (array)$dirs as $dir ) {
 894                                         $fileName = "$dir/$csCode.json";
 895                                         $data = $this->readJSONFile( $fileName );
 896
 897                                         foreach ( $data as $key => $item ) {
 898                                                 $this->mergeItem( $key, $csData[$key], $item );
 899                                         }
 900
 901                                         $deps[] = new FileDependency( $fileName );
 902                                 }
 903                         }
 904
 905                         # Merge non-JSON extension data
 906                         if ( isset( $extensionData[$csCode] ) ) {
 907                                 foreach ( $extensionData[$csCode] as $key => $item ) {
 908                                         $this->mergeItem( $key, $csData[$key], $item );
 909                                 }
 910                         }
 911
 912                         if ( $csCode === $code ) {
 913                                 # Merge core data into extension data
 914                                 foreach ( $coreData as $key => $item ) {
 915                                         $this->mergeItem( $key, $csData[$key], $item );
 916                                 }
 917                         } else {
 918                                 # Load the secondary localisation from the source file to
 919                                 # avoid infinite cycles on cyclic fallbacks
 920                                 $fbData = $this->readSourceFilesAndRegisterDeps( $csCode, $deps );
 921                                 if ( $fbData !== false ) {
 922                                         # Only merge the keys that make sense to merge
 923                                         foreach ( self::$allKeys as $key ) {
 924                                                 if ( !isset( $fbData[$key] ) ) {
 925                                                         continue;
 926                                                 }
 927
 928                                                 if ( is_null( $coreData[$key] ) || $this->isMergeableKey( $key ) ) {
 929                                                         $this->mergeItem( $key, $csData[$key], $fbData[$key] );
 930                                                 }
 931                                         }
 932                                 }
 933                         }
 934
 935                         # Allow extensions an opportunity to adjust the data for this
 936                         # fallback
 937                         Hooks::run( 'LocalisationCacheRecacheFallback', array( $this, $csCode, &$csData ) );
 938
 939                         # Merge the data for this fallback into the final array
 940                         if ( $csCode === $code ) {
 941                                 $allData = $csData;
 942                         } else {
 943                                 foreach ( self::$allKeys as $key ) {
 944                                         if ( !isset( $csData[$key] ) ) {
 945                                                 continue;
 946                                         }
 947
 948                                         if ( is_null( $allData[$key] ) || $this->isMergeableKey( $key ) ) {
 949                                                 $this->mergeItem( $key, $allData[$key], $csData[$key] );
 950                                         }
 951                                 }
 952                         }
 953                 }
 954
 955                 # Add cache dependencies for any referenced globals
 956                 $deps['wgExtensionMessagesFiles'] = new GlobalDependency( 'wgExtensionMessagesFiles' );
 957                 // $wgMessagesDirs is used in LocalisationCache::getMessagesDirs()
 958                 $deps['wgMessagesDirs'] = new GlobalDependency( 'wgMessagesDirs' );
 959                 $deps['version'] = new ConstantDependency( 'LocalisationCache::VERSION' );
 960
 961                 # Add dependencies to the cache entry
 962                 $allData['deps'] = $deps;
 963
 964                 # Replace spaces with underscores in namespace names
 965                 $allData['namespaceNames'] = str_replace( ' ', '_', $allData['namespaceNames'] );
 966
 967                 # And do the same for special page aliases. $page is an array.
 968                 foreach ( $allData['specialPageAliases'] as &$page ) {
 969                         $page = str_replace( ' ', '_', $page );
 970                 }
 971                 # Decouple the reference to prevent accidental damage
 972                 unset( $page );
 973
 974                 # If there were no plural rules, return an empty array
 975                 if ( $allData['pluralRules'] === null ) {
 976                         $allData['pluralRules'] = array();
 977                 }
 978                 if ( $allData['compiledPluralRules'] === null ) {
 979                         $allData['compiledPluralRules'] = array();
 980                 }
 981                 # If there were no plural rule types, return an empty array
 982                 if ( $allData['pluralRuleTypes'] === null ) {
 983                         $allData['pluralRuleTypes'] = array();
 984                 }
 985
 986                 # Set the list keys
 987                 $allData['list'] = array();
 988                 foreach ( self::$splitKeys as $key ) {
 989                         $allData['list'][$key] = array_keys( $allData[$key] );
 990                 }
 991                 # Run hooks
 992                 $purgeBlobs = true;
 993                 Hooks::run( 'LocalisationCacheRecache', array( $this, $code, &$allData, &$purgeBlobs ) );
 994
 995                 if ( is_null( $allData['namespaceNames'] ) ) {
 996                         throw new MWException( __METHOD__ . ': Localisation data failed sanity check! ' .
 997                                 'Check that your languages/messages/MessagesEn.php file is intact.' );
 998                 }
 999
1000                 # Set the preload key
1001                 $allData['preload'] = $this->buildPreload( $allData );
1002
1003                 # Save to the process cache and register the items loaded
1004                 $this->data[$code] = $allData;
1005                 foreach ( $allData as $key => $item ) {
1006                         $this->loadedItems[$code][$key] = true;
1007                 }
1008
1009                 # Save to the persistent cache
1010                 $this->store->startWrite( $code );
1011                 foreach ( $allData as $key => $value ) {
1012                         if ( in_array( $key, self::$splitKeys ) ) {
1013                                 foreach ( $value as $subkey => $subvalue ) {
1014                                         $this->store->set( "$key:$subkey", $subvalue );
1015                                 }
1016                         } else {
1017                                 $this->store->set( $key, $value );
1018                         }
1019                 }
1020                 $this->store->finishWrite();
1021
1022                 # Clear out the MessageBlobStore
1023                 # HACK: If using a null (i.e. disabled) storage backend, we
1024                 # can't write to the MessageBlobStore either
1025                 if ( $purgeBlobs && !$this->store instanceof LCStoreNull ) {
1026                         $blobStore = new MessageBlobStore();
1027                         $blobStore->clear();
1028                 }
1029
1030         }
1031
1032         /**
1033          * Build the preload item from the given pre-cache data.
1034          *
1035          * The preload item will be loaded automatically, improving performance
1036          * for the commonly-requested items it contains.
1037          * @param array $data
1038          * @return array
1039          */
1040         protected function buildPreload( $data ) {
1041                 $preload = array( 'messages' => array() );
1042                 foreach ( self::$preloadedKeys as $key ) {
1043                         $preload[$key] = $data[$key];
1044                 }
1045
1046                 foreach ( $data['preloadedMessages'] as $subkey ) {
1047                         if ( isset( $data['messages'][$subkey] ) ) {
1048                                 $subitem = $data['messages'][$subkey];
1049                         } else {
1050                                 $subitem = null;
1051                         }
1052                         $preload['messages'][$subkey] = $subitem;
1053                 }
1054
1055                 return $preload;
1056         }
1057
1058         /**
1059          * Unload the data for a given language from the object cache.
1060          * Reduces memory usage.
1061          * @param string $code
1062          */
1063         public function unload( $code ) {
1064                 unset( $this->data[$code] );
1065                 unset( $this->loadedItems[$code] );
1066                 unset( $this->loadedSubitems[$code] );
1067                 unset( $this->initialisedLangs[$code] );
1068                 unset( $this->shallowFallbacks[$code] );
1069
1070                 foreach ( $this->shallowFallbacks as $shallowCode => $fbCode ) {
1071                         if ( $fbCode === $code ) {
1072                                 $this->unload( $shallowCode );
1073                         }
1074                 }
1075         }
1076
1077         /**
1078          * Unload all data
1079          */
1080         public function unloadAll() {
1081                 foreach ( $this->initialisedLangs as $lang => $unused ) {
1082                         $this->unload( $lang );
1083                 }
1084         }
1085
1086         /**
1087          * Disable the storage backend
1088          */
1089         public function disableBackend() {
1090                 $this->store = new LCStoreNull;
1091                 $this->manualRecache = false;
1092         }
1093 }
1094
1095 /**
1096  * Interface for the persistence layer of LocalisationCache.
1097  *
1098  * The persistence layer is two-level hierarchical cache. The first level
1099  * is the language, the second level is the item or subitem.
1100  *
1101  * Since the data for a whole language is rebuilt in one operation, it needs
1102  * to have a fast and atomic method for deleting or replacing all of the
1103  * current data for a given language. The interface reflects this bulk update
1104  * operation. Callers writing to the cache must first call startWrite(), then
1105  * will call set() a couple of thousand times, then will call finishWrite()
1106  * to commit the operation. When finishWrite() is called, the cache is
1107  * expected to delete all data previously stored for that language.
1108  *
1109  * The values stored are PHP variables suitable for serialize(). Implementations
1110  * of LCStore are responsible for serializing and unserializing.
1111  */
1112 interface LCStore {
1113         /**
1114          * Get a value.
1115          * @param string $code Language code
1116          * @param string $key Cache key
1117          */
1118         function get( $code, $key );
1119
1120         /**
1121          * Start a write transaction.
1122          * @param string $code Language code
1123          */
1124         function startWrite( $code );
1125
1126         /**
1127          * Finish a write transaction.
1128          */
1129         function finishWrite();
1130
1131         /**
1132          * Set a key to a given value. startWrite() must be called before this
1133          * is called, and finishWrite() must be called afterwards.
1134          * @param string $key
1135          * @param mixed $value
1136          */
1137         function set( $key, $value );
1138 }
1139
1140 /**
1141  * LCStore implementation which uses the standard DB functions to store data.
1142  * This will work on any MediaWiki installation.
1143  */
1144 class LCStoreDB implements LCStore {
1145         private $currentLang;
1146         private $writesDone = false;
1147
1148         /** @var DatabaseBase */
1149         private $dbw;
1150         /** @var array */
1151         private $batch = array();
1152
1153         private $readOnly = false;
1154
1155         public function get( $code, $key ) {
1156                 if ( $this->writesDone ) {
1157                         $db = wfGetDB( DB_MASTER );
1158                 } else {
1159                         $db = wfGetDB( DB_SLAVE );
1160                 }
1161                 $row = $db->selectRow( 'l10n_cache', array( 'lc_value' ),
1162                         array( 'lc_lang' => $code, 'lc_key' => $key ), __METHOD__ );
1163                 if ( $row ) {
1164                         return unserialize( $db->decodeBlob( $row->lc_value ) );
1165                 } else {
1166                         return null;
1167                 }
1168         }
1169
1170         public function startWrite( $code ) {
1171                 if ( $this->readOnly ) {
1172                         return;
1173                 } elseif ( !$code ) {
1174                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
1175                 }
1176
1177                 $this->dbw = wfGetDB( DB_MASTER );
1178
1179                 $this->currentLang = $code;
1180                 $this->batch = array();
1181         }
1182
1183         public function finishWrite() {
1184                 if ( $this->readOnly ) {
1185                         return;
1186                 } elseif ( is_null( $this->currentLang ) ) {
1187                         throw new MWException( __CLASS__ . ': must call startWrite() before finishWrite()' );
1188                 }
1189
1190                 $this->dbw->begin( __METHOD__ );
1191                 try {
1192                         $this->dbw->delete( 'l10n_cache',
1193                                 array( 'lc_lang' => $this->currentLang ), __METHOD__ );
1194                         foreach ( array_chunk( $this->batch, 500 ) as $rows ) {
1195                                 $this->dbw->insert( 'l10n_cache', $rows, __METHOD__ );
1196                         }
1197                         $this->writesDone = true;
1198                 } catch ( DBQueryError $e ) {
1199                         if ( $this->dbw->wasReadOnlyError() ) {
1200                                 $this->readOnly = true; // just avoid site down time
1201                         } else {
1202                                 throw $e;
1203                         }
1204                 }
1205                 $this->dbw->commit( __METHOD__ );
1206
1207                 $this->currentLang = null;
1208                 $this->batch = array();
1209         }
1210
1211         public function set( $key, $value ) {
1212                 if ( $this->readOnly ) {
1213                         return;
1214                 } elseif ( is_null( $this->currentLang ) ) {
1215                         throw new MWException( __CLASS__ . ': must call startWrite() before set()' );
1216                 }
1217
1218                 $this->batch[] = array(
1219                         'lc_lang' => $this->currentLang,
1220                         'lc_key' => $key,
1221                         'lc_value' => $this->dbw->encodeBlob( serialize( $value ) ) );
1222         }
1223 }
1224
1225 /**
1226  * LCStore implementation which stores data as a collection of CDB files in the
1227  * directory given by $wgCacheDirectory. If $wgCacheDirectory is not set, this
1228  * will throw an exception.
1229  *
1230  * Profiling indicates that on Linux, this implementation outperforms MySQL if
1231  * the directory is on a local filesystem and there is ample kernel cache
1232  * space. The performance advantage is greater when the DBA extension is
1233  * available than it is with the PHP port.
1234  *
1235  * See Cdb.php and http://cr.yp.to/cdb.html
1236  */
1237 class LCStoreCDB implements LCStore {
1238         /** @var CdbReader[] */
1239         private $readers;
1240
1241         /** @var CdbWriter */
1242         private $writer;
1243
1244         /** @var string Current language code */
1245         private $currentLang;
1246
1247         /** @var bool|string Cache directory. False if not set */
1248         private $directory;
1249
1250         function __construct( $conf = array() ) {
1251                 global $wgCacheDirectory;
1252
1253                 if ( isset( $conf['directory'] ) ) {
1254                         $this->directory = $conf['directory'];
1255                 } else {
1256                         $this->directory = $wgCacheDirectory;
1257                 }
1258         }
1259
1260         public function get( $code, $key ) {
1261                 if ( !isset( $this->readers[$code] ) ) {
1262                         $fileName = $this->getFileName( $code );
1263
1264                         $this->readers[$code] = false;
1265                         if ( file_exists( $fileName ) ) {
1266                                 try {
1267                                         $this->readers[$code] = CdbReader::open( $fileName );
1268                                 } catch ( CdbException $e ) {
1269                                         wfDebug( __METHOD__ . ": unable to open cdb file for reading\n" );
1270                                 }
1271                         }
1272                 }
1273
1274                 if ( !$this->readers[$code] ) {
1275                         return null;
1276                 } else {
1277                         $value = false;
1278                         try {
1279                                 $value = $this->readers[$code]->get( $key );
1280                         } catch ( CdbException $e ) {
1281                                 wfDebug( __METHOD__ . ": CdbException caught, error message was "
1282                                         . $e->getMessage() . "\n" );
1283                         }
1284                         if ( $value === false ) {
1285                                 return null;
1286                         }
1287
1288                         return unserialize( $value );
1289                 }
1290         }
1291
1292         public function startWrite( $code ) {
1293                 if ( !file_exists( $this->directory ) ) {
1294                         if ( !wfMkdirParents( $this->directory, null, __METHOD__ ) ) {
1295                                 throw new MWException( "Unable to create the localisation store " .
1296                                         "directory \"{$this->directory}\"" );
1297                         }
1298                 }
1299
1300                 // Close reader to stop permission errors on write
1301                 if ( !empty( $this->readers[$code] ) ) {
1302                         $this->readers[$code]->close();
1303                 }
1304
1305                 try {
1306                         $this->writer = CdbWriter::open( $this->getFileName( $code ) );
1307                 } catch ( CdbException $e ) {
1308                         throw new MWException( $e->getMessage() );
1309                 }
1310                 $this->currentLang = $code;
1311         }
1312
1313         public function finishWrite() {
1314                 // Close the writer
1315                 try {
1316                         $this->writer->close();
1317                 } catch ( CdbException $e ) {
1318                         throw new MWException( $e->getMessage() );
1319                 }
1320                 $this->writer = null;
1321                 unset( $this->readers[$this->currentLang] );
1322                 $this->currentLang = null;
1323         }
1324
1325         public function set( $key, $value ) {
1326                 if ( is_null( $this->writer ) ) {
1327                         throw new MWException( __CLASS__ . ': must call startWrite() before calling set()' );
1328                 }
1329                 try {
1330                         $this->writer->set( $key, serialize( $value ) );
1331                 } catch ( CdbException $e ) {
1332                         throw new MWException( $e->getMessage() );
1333                 }
1334         }
1335
1336         protected function getFileName( $code ) {
1337                 if ( strval( $code ) === '' || strpos( $code, '/' ) !== false ) {
1338                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
1339                 }
1340
1341                 return "{$this->directory}/l10n_cache-$code.cdb";
1342         }
1343 }
1344
1345 /**
1346  * Null store backend, used to avoid DB errors during install
1347  */
1348 class LCStoreNull implements LCStore {
1349         public function get( $code, $key ) {
1350                 return null;
1351         }
1352
1353         public function startWrite( $code ) {
1354         }
1355
1356         public function finishWrite() {
1357         }
1358
1359         public function set( $key, $value ) {
1360         }
1361 }
1362
1363 /**
1364  * A localisation cache optimised for loading large amounts of data for many
1365  * languages. Used by rebuildLocalisationCache.php.
1366  */
1367 class LocalisationCacheBulkLoad extends LocalisationCache {
1368         /**
1369          * A cache of the contents of data files.
1370          * Core files are serialized to avoid using ~1GB of RAM during a recache.
1371          */
1372         private $fileCache = array();
1373
1374         /**
1375          * Most recently used languages. Uses the linked-list aspect of PHP hashtables
1376          * to keep the most recently used language codes at the end of the array, and
1377          * the language codes that are ready to be deleted at the beginning.
1378          */
1379         private $mruLangs = array();
1380
1381         /**
1382          * Maximum number of languages that may be loaded into $this->data
1383          */
1384         private $maxLoadedLangs = 10;
1385
1386         /**
1387          * @param string $fileName
1388          * @param string $fileType
1389          * @return array|mixed
1390          */
1391         protected function readPHPFile( $fileName, $fileType ) {
1392                 $serialize = $fileType === 'core';
1393                 if ( !isset( $this->fileCache[$fileName][$fileType] ) ) {
1394                         $data = parent::readPHPFile( $fileName, $fileType );
1395
1396                         if ( $serialize ) {
1397                                 $encData = serialize( $data );
1398                         } else {
1399                                 $encData = $data;
1400                         }
1401
1402                         $this->fileCache[$fileName][$fileType] = $encData;
1403
1404                         return $data;
1405                 } elseif ( $serialize ) {
1406                         return unserialize( $this->fileCache[$fileName][$fileType] );
1407                 } else {
1408                         return $this->fileCache[$fileName][$fileType];
1409                 }
1410         }
1411
1412         /**
1413          * @param string $code
1414          * @param string $key
1415          * @return mixed
1416          */
1417         public function getItem( $code, $key ) {
1418                 unset( $this->mruLangs[$code] );
1419                 $this->mruLangs[$code] = true;
1420
1421                 return parent::getItem( $code, $key );
1422         }
1423
1424         /**
1425          * @param string $code
1426          * @param string $key
1427          * @param string $subkey
1428          * @return mixed
1429          */
1430         public function getSubitem( $code, $key, $subkey ) {
1431                 unset( $this->mruLangs[$code] );
1432                 $this->mruLangs[$code] = true;
1433
1434                 return parent::getSubitem( $code, $key, $subkey );
1435         }
1436
1437         /**
1438          * @param string $code
1439          */
1440         public function recache( $code ) {
1441                 parent::recache( $code );
1442                 unset( $this->mruLangs[$code] );
1443                 $this->mruLangs[$code] = true;
1444                 $this->trimCache();
1445         }
1446
1447         /**
1448          * @param string $code
1449          */
1450         public function unload( $code ) {
1451                 unset( $this->mruLangs[$code] );
1452                 parent::unload( $code );
1453         }
1454
1455         /**
1456          * Unload cached languages until there are less than $this->maxLoadedLangs
1457          */
1458         protected function trimCache() {
1459                 while ( count( $this->data ) > $this->maxLoadedLangs && count( $this->mruLangs ) ) {
1460                         reset( $this->mruLangs );
1461                         $code = key( $this->mruLangs );
1462                         wfDebug( __METHOD__ . ": unloading $code\n" );
1463                         $this->unload( $code );
1464                 }
1465         }
1466 }