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 use CLDRPluralRuleParser\Evaluator;
  27
  28 /**
  29  * Class for caching the contents of localisation files, Messages*.php
  30  * and *.i18n.php.
  31  *
  32  * An instance of this class is available using Language::getLocalisationCache().
  33  *
  34  * The values retrieved from here are merged, containing items from extension
  35  * files, core messages files and the language fallback sequence (e.g. zh-cn ->
  36  * zh-hans -> en ). Some common errors are corrected, for example namespace
  37  * names with spaces instead of underscores, but heavyweight processing, such
  38  * as grammatical transformation, is done by the caller.
  39  */
  40 class LocalisationCache {
  41         const VERSION = 3;
  42
  43         /** Configuration associative array */
  44         private $conf;
  45
  46         /**
  47          * True if recaching should only be done on an explicit call to recache().
  48          * Setting this reduces the overhead of cache freshness checking, which
  49          * requires doing a stat() for every extension i18n file.
  50          */
  51         private $manualRecache = false;
  52
  53         /**
  54          * True to treat all files as expired until they are regenerated by this object.
  55          */
  56         private $forceRecache = false;
  57
  58         /**
  59          * The cache data. 3-d array, where the first key is the language code,
  60          * the second key is the item key e.g. 'messages', and the third key is
  61          * an item specific subkey index. Some items are not arrays and so for those
  62          * items, there are no subkeys.
  63          */
  64         protected $data = array();
  65
  66         /**
  67          * The persistent store object. An instance of LCStore.
  68          *
  69          * @var LCStore
  70          */
  71         private $store;
  72
  73         /**
  74          * A 2-d associative array, code/key, where presence indicates that the item
  75          * is loaded. Value arbitrary.
  76          *
  77          * For split items, if set, this indicates that all of the subitems have been
  78          * loaded.
  79          */
  80         private $loadedItems = array();
  81
  82         /**
  83          * A 3-d associative array, code/key/subkey, where presence indicates that
  84          * the subitem is loaded. Only used for the split items, i.e. messages.
  85          */
  86         private $loadedSubitems = array();
  87
  88         /**
  89          * An array where presence of a key indicates that that language has been
  90          * initialised. Initialisation includes checking for cache expiry and doing
  91          * any necessary updates.
  92          */
  93         private $initialisedLangs = array();
  94
  95         /**
  96          * An array mapping non-existent pseudo-languages to fallback languages. This
  97          * is filled by initShallowFallback() when data is requested from a language
  98          * that lacks a Messages*.php file.
  99          */
 100         private $shallowFallbacks = array();
 101
 102         /**
 103          * An array where the keys are codes that have been recached by this instance.
 104          */
 105         private $recachedLangs = array();
 106
 107         /**
 108          * All item keys
 109          */
 110         static public $allKeys = array(
 111                 'fallback', 'namespaceNames', 'bookstoreList',
 112                 'magicWords', 'messages', 'rtl', 'capitalizeAllNouns', 'digitTransformTable',
 113                 'separatorTransformTable', 'fallback8bitEncoding', 'linkPrefixExtension',
 114                 'linkTrail', 'linkPrefixCharset', 'namespaceAliases',
 115                 'dateFormats', 'datePreferences', 'datePreferenceMigrationMap',
 116                 'defaultDateFormat', 'extraUserToggles', 'specialPageAliases',
 117                 'imageFiles', 'preloadedMessages', 'namespaceGenderAliases',
 118                 'digitGroupingPattern', 'pluralRules', 'pluralRuleTypes', 'compiledPluralRules',
 119         );
 120
 121         /**
 122          * Keys for items which consist of associative arrays, which may be merged
 123          * by a fallback sequence.
 124          */
 125         static public $mergeableMapKeys = array( 'messages', 'namespaceNames',
 126                 'dateFormats', 'imageFiles', 'preloadedMessages'
 127         );
 128
 129         /**
 130          * Keys for items which are a numbered array.
 131          */
 132         static public $mergeableListKeys = array( 'extraUserToggles' );
 133
 134         /**
 135          * Keys for items which contain an array of arrays of equivalent aliases
 136          * for each subitem. The aliases may be merged by a fallback sequence.
 137          */
 138         static public $mergeableAliasListKeys = array( 'specialPageAliases' );
 139
 140         /**
 141          * Keys for items which contain an associative array, and may be merged if
 142          * the primary value contains the special array key "inherit". That array
 143          * key is removed after the first merge.
 144          */
 145         static public $optionalMergeKeys = array( 'bookstoreList' );
 146
 147         /**
 148          * Keys for items that are formatted like $magicWords
 149          */
 150         static public $magicWordKeys = array( 'magicWords' );
 151
 152         /**
 153          * Keys for items where the subitems are stored in the backend separately.
 154          */
 155         static public $splitKeys = array( 'messages' );
 156
 157         /**
 158          * Keys which are loaded automatically by initLanguage()
 159          */
 160         static public $preloadedKeys = array( 'dateFormats', 'namespaceNames' );
 161
 162         /**
 163          * Associative array of cached plural rules. The key is the language code,
 164          * the value is an array of plural rules for that language.
 165          */
 166         private $pluralRules = null;
 167
 168         /**
 169          * Associative array of cached plural rule types. The key is the language
 170          * code, the value is an array of plural rule types for that language. For
 171          * example, $pluralRuleTypes['ar'] = ['zero', 'one', 'two', 'few', 'many'].
 172          * The index for each rule type matches the index for the rule in
 173          * $pluralRules, thus allowing correlation between the two. The reason we
 174          * don't just use the type names as the keys in $pluralRules is because
 175          * Language::convertPlural applies the rules based on numeric order (or
 176          * explicit numeric parameter), not based on the name of the rule type. For
 177          * example, {{plural:count|wordform1|wordform2|wordform3}}, rather than
 178          * {{plural:count|one=wordform1|two=wordform2|many=wordform3}}.
 179          */
 180         private $pluralRuleTypes = null;
 181
 182         private $mergeableKeys = null;
 183
 184         /**
 185          * Constructor.
 186          * For constructor parameters, see the documentation in DefaultSettings.php
 187          * for $wgLocalisationCacheConf.
 188          *
 189          * @param array $conf
 190          * @throws MWException
 191          */
 192         function __construct( $conf ) {
 193                 global $wgCacheDirectory;
 194
 195                 $this->conf = $conf;
 196                 $storeConf = array();
 197                 if ( !empty( $conf['storeClass'] ) ) {
 198                         $storeClass = $conf['storeClass'];
 199                 } else {
 200                         switch ( $conf['store'] ) {
 201                                 case 'files':
 202                                 case 'file':
 203                                         $storeClass = 'LCStoreCDB';
 204                                         break;
 205                                 case 'db':
 206                                         $storeClass = 'LCStoreDB';
 207                                         break;
 208                                 case 'array':
 209                                         $storeClass = 'LCStoreStaticArray';
 210                                         break;
 211                                 case 'detect':
 212                                         $storeClass = $wgCacheDirectory ? 'LCStoreCDB' : 'LCStoreDB';
 213                                         break;
 214                                 default:
 215                                         throw new MWException(
 216                                                 'Please set $wgLocalisationCacheConf[\'store\'] to something sensible.' );
 217                         }
 218                 }
 219
 220                 wfDebugLog( 'caches', get_class( $this ) . ": using store $storeClass" );
 221                 if ( !empty( $conf['storeDirectory'] ) ) {
 222                         $storeConf['directory'] = $conf['storeDirectory'];
 223                 }
 224
 225                 $this->store = new $storeClass( $storeConf );
 226                 foreach ( array( 'manualRecache', 'forceRecache' ) as $var ) {
 227                         if ( isset( $conf[$var] ) ) {
 228                                 $this->$var = $conf[$var];
 229                         }
 230                 }
 231         }
 232
 233         /**
 234          * Returns true if the given key is mergeable, that is, if it is an associative
 235          * array which can be merged through a fallback sequence.
 236          * @param string $key
 237          * @return bool
 238          */
 239         public function isMergeableKey( $key ) {
 240                 if ( $this->mergeableKeys === null ) {
 241                         $this->mergeableKeys = array_flip( array_merge(
 242                                 self::$mergeableMapKeys,
 243                                 self::$mergeableListKeys,
 244                                 self::$mergeableAliasListKeys,
 245                                 self::$optionalMergeKeys,
 246                                 self::$magicWordKeys
 247                         ) );
 248                 }
 249
 250                 return isset( $this->mergeableKeys[$key] );
 251         }
 252
 253         /**
 254          * Get a cache item.
 255          *
 256          * Warning: this may be slow for split items (messages), since it will
 257          * need to fetch all of the subitems from the cache individually.
 258          * @param string $code
 259          * @param string $key
 260          * @return mixed
 261          */
 262         public function getItem( $code, $key ) {
 263                 if ( !isset( $this->loadedItems[$code][$key] ) ) {
 264                         $this->loadItem( $code, $key );
 265                 }
 266
 267                 if ( $key === 'fallback' && isset( $this->shallowFallbacks[$code] ) ) {
 268                         return $this->shallowFallbacks[$code];
 269                 }
 270
 271                 return $this->data[$code][$key];
 272         }
 273
 274         /**
 275          * Get a subitem, for instance a single message for a given language.
 276          * @param string $code
 277          * @param string $key
 278          * @param string $subkey
 279          * @return mixed|null
 280          */
 281         public function getSubitem( $code, $key, $subkey ) {
 282                 if ( !isset( $this->loadedSubitems[$code][$key][$subkey] ) &&
 283                         !isset( $this->loadedItems[$code][$key] )
 284                 ) {
 285                         $this->loadSubitem( $code, $key, $subkey );
 286                 }
 287
 288                 if ( isset( $this->data[$code][$key][$subkey] ) ) {
 289                         return $this->data[$code][$key][$subkey];
 290                 } else {
 291                         return null;
 292                 }
 293         }
 294
 295         /**
 296          * Get the list of subitem keys for a given item.
 297          *
 298          * This is faster than array_keys($lc->getItem(...)) for the items listed in
 299          * self::$splitKeys.
 300          *
 301          * Will return null if the item is not found, or false if the item is not an
 302          * array.
 303          * @param string $code
 304          * @param string $key
 305          * @return bool|null|string
 306          */
 307         public function getSubitemList( $code, $key ) {
 308                 if ( in_array( $key, self::$splitKeys ) ) {
 309                         return $this->getSubitem( $code, 'list', $key );
 310                 } else {
 311                         $item = $this->getItem( $code, $key );
 312                         if ( is_array( $item ) ) {
 313                                 return array_keys( $item );
 314                         } else {
 315                                 return false;
 316                         }
 317                 }
 318         }
 319
 320         /**
 321          * Load an item into the cache.
 322          * @param string $code
 323          * @param string $key
 324          */
 325         protected function loadItem( $code, $key ) {
 326                 if ( !isset( $this->initialisedLangs[$code] ) ) {
 327                         $this->initLanguage( $code );
 328                 }
 329
 330                 // Check to see if initLanguage() loaded it for us
 331                 if ( isset( $this->loadedItems[$code][$key] ) ) {
 332                         return;
 333                 }
 334
 335                 if ( isset( $this->shallowFallbacks[$code] ) ) {
 336                         $this->loadItem( $this->shallowFallbacks[$code], $key );
 337
 338                         return;
 339                 }
 340
 341                 if ( in_array( $key, self::$splitKeys ) ) {
 342                         $subkeyList = $this->getSubitem( $code, 'list', $key );
 343                         foreach ( $subkeyList as $subkey ) {
 344                                 if ( isset( $this->data[$code][$key][$subkey] ) ) {
 345                                         continue;
 346                                 }
 347                                 $this->data[$code][$key][$subkey] = $this->getSubitem( $code, $key, $subkey );
 348                         }
 349                 } else {
 350                         $this->data[$code][$key] = $this->store->get( $code, $key );
 351                 }
 352
 353                 $this->loadedItems[$code][$key] = true;
 354         }
 355
 356         /**
 357          * Load a subitem into the cache
 358          * @param string $code
 359          * @param string $key
 360          * @param string $subkey
 361          */
 362         protected function loadSubitem( $code, $key, $subkey ) {
 363                 if ( !in_array( $key, self::$splitKeys ) ) {
 364                         $this->loadItem( $code, $key );
 365
 366                         return;
 367                 }
 368
 369                 if ( !isset( $this->initialisedLangs[$code] ) ) {
 370                         $this->initLanguage( $code );
 371                 }
 372
 373                 // Check to see if initLanguage() loaded it for us
 374                 if ( isset( $this->loadedItems[$code][$key] ) ||
 375                         isset( $this->loadedSubitems[$code][$key][$subkey] )
 376                 ) {
 377                         return;
 378                 }
 379
 380                 if ( isset( $this->shallowFallbacks[$code] ) ) {
 381                         $this->loadSubitem( $this->shallowFallbacks[$code], $key, $subkey );
 382
 383                         return;
 384                 }
 385
 386                 $value = $this->store->get( $code, "$key:$subkey" );
 387                 $this->data[$code][$key][$subkey] = $value;
 388                 $this->loadedSubitems[$code][$key][$subkey] = true;
 389         }
 390
 391         /**
 392          * Returns true if the cache identified by $code is missing or expired.
 393          *
 394          * @param string $code
 395          *
 396          * @return bool
 397          */
 398         public function isExpired( $code ) {
 399                 if ( $this->forceRecache && !isset( $this->recachedLangs[$code] ) ) {
 400                         wfDebug( __METHOD__ . "($code): forced reload\n" );
 401
 402                         return true;
 403                 }
 404
 405                 $deps = $this->store->get( $code, 'deps' );
 406                 $keys = $this->store->get( $code, 'list' );
 407                 $preload = $this->store->get( $code, 'preload' );
 408                 // Different keys may expire separately for some stores
 409                 if ( $deps === null || $keys === null || $preload === null ) {
 410                         wfDebug( __METHOD__ . "($code): cache missing, need to make one\n" );
 411
 412                         return true;
 413                 }
 414
 415                 foreach ( $deps as $dep ) {
 416                         // Because we're unserializing stuff from cache, we
 417                         // could receive objects of classes that don't exist
 418                         // anymore (e.g. uninstalled extensions)
 419                         // When this happens, always expire the cache
 420                         if ( !$dep instanceof CacheDependency || $dep->isExpired() ) {
 421                                 wfDebug( __METHOD__ . "($code): cache for $code expired due to " .
 422                                         get_class( $dep ) . "\n" );
 423
 424                                 return true;
 425                         }
 426                 }
 427
 428                 return false;
 429         }
 430
 431         /**
 432          * Initialise a language in this object. Rebuild the cache if necessary.
 433          * @param string $code
 434          * @throws MWException
 435          */
 436         protected function initLanguage( $code ) {
 437                 if ( isset( $this->initialisedLangs[$code] ) ) {
 438                         return;
 439                 }
 440
 441                 $this->initialisedLangs[$code] = true;
 442
 443                 # If the code is of the wrong form for a Messages*.php file, do a shallow fallback
 444                 if ( !Language::isValidBuiltInCode( $code ) ) {
 445                         $this->initShallowFallback( $code, 'en' );
 446
 447                         return;
 448                 }
 449
 450                 # Recache the data if necessary
 451                 if ( !$this->manualRecache && $this->isExpired( $code ) ) {
 452                         if ( Language::isSupportedLanguage( $code ) ) {
 453                                 $this->recache( $code );
 454                         } elseif ( $code === 'en' ) {
 455                                 throw new MWException( 'MessagesEn.php is missing.' );
 456                         } else {
 457                                 $this->initShallowFallback( $code, 'en' );
 458                         }
 459
 460                         return;
 461                 }
 462
 463                 # Preload some stuff
 464                 $preload = $this->getItem( $code, 'preload' );
 465                 if ( $preload === null ) {
 466                         if ( $this->manualRecache ) {
 467                                 // No Messages*.php file. Do shallow fallback to en.
 468                                 if ( $code === 'en' ) {
 469                                         throw new MWException( 'No localisation cache found for English. ' .
 470                                                 'Please run maintenance/rebuildLocalisationCache.php.' );
 471                                 }
 472                                 $this->initShallowFallback( $code, 'en' );
 473
 474                                 return;
 475                         } else {
 476                                 throw new MWException( 'Invalid or missing localisation cache.' );
 477                         }
 478                 }
 479                 $this->data[$code] = $preload;
 480                 foreach ( $preload as $key => $item ) {
 481                         if ( in_array( $key, self::$splitKeys ) ) {
 482                                 foreach ( $item as $subkey => $subitem ) {
 483                                         $this->loadedSubitems[$code][$key][$subkey] = true;
 484                                 }
 485                         } else {
 486                                 $this->loadedItems[$code][$key] = true;
 487                         }
 488                 }
 489         }
 490
 491         /**
 492          * Create a fallback from one language to another, without creating a
 493          * complete persistent cache.
 494          * @param string $primaryCode
 495          * @param string $fallbackCode
 496          */
 497         public function initShallowFallback( $primaryCode, $fallbackCode ) {
 498                 $this->data[$primaryCode] =& $this->data[$fallbackCode];
 499                 $this->loadedItems[$primaryCode] =& $this->loadedItems[$fallbackCode];
 500                 $this->loadedSubitems[$primaryCode] =& $this->loadedSubitems[$fallbackCode];
 501                 $this->shallowFallbacks[$primaryCode] = $fallbackCode;
 502         }
 503
 504         /**
 505          * Read a PHP file containing localisation data.
 506          * @param string $_fileName
 507          * @param string $_fileType
 508          * @throws MWException
 509          * @return array
 510          */
 511         protected function readPHPFile( $_fileName, $_fileType ) {
 512                 // Disable APC caching
 513                 MediaWiki\suppressWarnings();
 514                 $_apcEnabled = ini_set( 'apc.cache_by_default', '0' );
 515                 MediaWiki\restoreWarnings();
 516
 517                 include $_fileName;
 518
 519                 MediaWiki\suppressWarnings();
 520                 ini_set( 'apc.cache_by_default', $_apcEnabled );
 521                 MediaWiki\restoreWarnings();
 522
 523                 if ( $_fileType == 'core' || $_fileType == 'extension' ) {
 524                         $data = compact( self::$allKeys );
 525                 } elseif ( $_fileType == 'aliases' ) {
 526                         $data = compact( 'aliases' );
 527                 } else {
 528                         throw new MWException( __METHOD__ . ": Invalid file type: $_fileType" );
 529                 }
 530
 531                 return $data;
 532         }
 533
 534         /**
 535          * Read a JSON file containing localisation messages.
 536          * @param string $fileName Name of file to read
 537          * @throws MWException If there is a syntax error in the JSON file
 538          * @return array Array with a 'messages' key, or empty array if the file doesn't exist
 539          */
 540         public function readJSONFile( $fileName ) {
 541
 542                 if ( !is_readable( $fileName ) ) {
 543                         return array();
 544                 }
 545
 546                 $json = file_get_contents( $fileName );
 547                 if ( $json === false ) {
 548                         return array();
 549                 }
 550
 551                 $data = FormatJson::decode( $json, true );
 552                 if ( $data === null ) {
 553
 554                         throw new MWException( __METHOD__ . ": Invalid JSON file: $fileName" );
 555                 }
 556
 557                 // Remove keys starting with '@', they're reserved for metadata and non-message data
 558                 foreach ( $data as $key => $unused ) {
 559                         if ( $key === '' || $key[0] === '@' ) {
 560                                 unset( $data[$key] );
 561                         }
 562                 }
 563
 564                 // The JSON format only supports messages, none of the other variables, so wrap the data
 565                 return array( 'messages' => $data );
 566         }
 567
 568         /**
 569          * Get the compiled plural rules for a given language from the XML files.
 570          * @since 1.20
 571          * @param string $code
 572          * @return array|null
 573          */
 574         public function getCompiledPluralRules( $code ) {
 575                 $rules = $this->getPluralRules( $code );
 576                 if ( $rules === null ) {
 577                         return null;
 578                 }
 579                 try {
 580                         $compiledRules = Evaluator::compile( $rules );
 581                 } catch ( CLDRPluralRuleError $e ) {
 582                         wfDebugLog( 'l10n', $e->getMessage() );
 583
 584                         return array();
 585                 }
 586
 587                 return $compiledRules;
 588         }
 589
 590         /**
 591          * Get the plural rules for a given language from the XML files.
 592          * Cached.
 593          * @since 1.20
 594          * @param string $code
 595          * @return array|null
 596          */
 597         public function getPluralRules( $code ) {
 598                 if ( $this->pluralRules === null ) {
 599                         $this->loadPluralFiles();
 600                 }
 601                 if ( !isset( $this->pluralRules[$code] ) ) {
 602                         return null;
 603                 } else {
 604                         return $this->pluralRules[$code];
 605                 }
 606         }
 607
 608         /**
 609          * Get the plural rule types for a given language from the XML files.
 610          * Cached.
 611          * @since 1.22
 612          * @param string $code
 613          * @return array|null
 614          */
 615         public function getPluralRuleTypes( $code ) {
 616                 if ( $this->pluralRuleTypes === null ) {
 617                         $this->loadPluralFiles();
 618                 }
 619                 if ( !isset( $this->pluralRuleTypes[$code] ) ) {
 620                         return null;
 621                 } else {
 622                         return $this->pluralRuleTypes[$code];
 623                 }
 624         }
 625
 626         /**
 627          * Load the plural XML files.
 628          */
 629         protected function loadPluralFiles() {
 630                 global $IP;
 631                 $cldrPlural = "$IP/languages/data/plurals.xml";
 632                 $mwPlural = "$IP/languages/data/plurals-mediawiki.xml";
 633                 // Load CLDR plural rules
 634                 $this->loadPluralFile( $cldrPlural );
 635                 if ( file_exists( $mwPlural ) ) {
 636                         // Override or extend
 637                         $this->loadPluralFile( $mwPlural );
 638                 }
 639         }
 640
 641         /**
 642          * Load a plural XML file with the given filename, compile the relevant
 643          * rules, and save the compiled rules in a process-local cache.
 644          *
 645          * @param string $fileName
 646          * @throws MWException
 647          */
 648         protected function loadPluralFile( $fileName ) {
 649                 // Use file_get_contents instead of DOMDocument::load (T58439)
 650                 $xml = file_get_contents( $fileName );
 651                 if ( !$xml ) {
 652                         throw new MWException( "Unable to read plurals file $fileName" );
 653                 }
 654                 $doc = new DOMDocument;
 655                 $doc->loadXML( $xml );
 656                 $rulesets = $doc->getElementsByTagName( "pluralRules" );
 657                 foreach ( $rulesets as $ruleset ) {
 658                         $codes = $ruleset->getAttribute( 'locales' );
 659                         $rules = array();
 660                         $ruleTypes = array();
 661                         $ruleElements = $ruleset->getElementsByTagName( "pluralRule" );
 662                         foreach ( $ruleElements as $elt ) {
 663                                 $ruleType = $elt->getAttribute( 'count' );
 664                                 if ( $ruleType === 'other' ) {
 665                                         // Don't record "other" rules, which have an empty condition
 666                                         continue;
 667                                 }
 668                                 $rules[] = $elt->nodeValue;
 669                                 $ruleTypes[] = $ruleType;
 670                         }
 671                         foreach ( explode( ' ', $codes ) as $code ) {
 672                                 $this->pluralRules[$code] = $rules;
 673                                 $this->pluralRuleTypes[$code] = $ruleTypes;
 674                         }
 675                 }
 676         }
 677
 678         /**
 679          * Read the data from the source files for a given language, and register
 680          * the relevant dependencies in the $deps array. If the localisation
 681          * exists, the data array is returned, otherwise false is returned.
 682          *
 683          * @param string $code
 684          * @param array $deps
 685          * @return array
 686          */
 687         protected function readSourceFilesAndRegisterDeps( $code, &$deps ) {
 688                 global $IP;
 689
 690                 // This reads in the PHP i18n file with non-messages l10n data
 691                 $fileName = Language::getMessagesFileName( $code );
 692                 if ( !file_exists( $fileName ) ) {
 693                         $data = array();
 694                 } else {
 695                         $deps[] = new FileDependency( $fileName );
 696                         $data = $this->readPHPFile( $fileName, 'core' );
 697                 }
 698
 699                 # Load CLDR plural rules for JavaScript
 700                 $data['pluralRules'] = $this->getPluralRules( $code );
 701                 # And for PHP
 702                 $data['compiledPluralRules'] = $this->getCompiledPluralRules( $code );
 703                 # Load plural rule types
 704                 $data['pluralRuleTypes'] = $this->getPluralRuleTypes( $code );
 705
 706                 $deps['plurals'] = new FileDependency( "$IP/languages/data/plurals.xml" );
 707                 $deps['plurals-mw'] = new FileDependency( "$IP/languages/data/plurals-mediawiki.xml" );
 708
 709                 return $data;
 710         }
 711
 712         /**
 713          * Merge two localisation values, a primary and a fallback, overwriting the
 714          * primary value in place.
 715          * @param string $key
 716          * @param mixed $value
 717          * @param mixed $fallbackValue
 718          */
 719         protected function mergeItem( $key, &$value, $fallbackValue ) {
 720                 if ( !is_null( $value ) ) {
 721                         if ( !is_null( $fallbackValue ) ) {
 722                                 if ( in_array( $key, self::$mergeableMapKeys ) ) {
 723                                         $value = $value + $fallbackValue;
 724                                 } elseif ( in_array( $key, self::$mergeableListKeys ) ) {
 725                                         $value = array_unique( array_merge( $fallbackValue, $value ) );
 726                                 } elseif ( in_array( $key, self::$mergeableAliasListKeys ) ) {
 727                                         $value = array_merge_recursive( $value, $fallbackValue );
 728                                 } elseif ( in_array( $key, self::$optionalMergeKeys ) ) {
 729                                         if ( !empty( $value['inherit'] ) ) {
 730                                                 $value = array_merge( $fallbackValue, $value );
 731                                         }
 732
 733                                         if ( isset( $value['inherit'] ) ) {
 734                                                 unset( $value['inherit'] );
 735                                         }
 736                                 } elseif ( in_array( $key, self::$magicWordKeys ) ) {
 737                                         $this->mergeMagicWords( $value, $fallbackValue );
 738                                 }
 739                         }
 740                 } else {
 741                         $value = $fallbackValue;
 742                 }
 743         }
 744
 745         /**
 746          * @param mixed $value
 747          * @param mixed $fallbackValue
 748          */
 749         protected function mergeMagicWords( &$value, $fallbackValue ) {
 750                 foreach ( $fallbackValue as $magicName => $fallbackInfo ) {
 751                         if ( !isset( $value[$magicName] ) ) {
 752                                 $value[$magicName] = $fallbackInfo;
 753                         } else {
 754                                 $oldSynonyms = array_slice( $fallbackInfo, 1 );
 755                                 $newSynonyms = array_slice( $value[$magicName], 1 );
 756                                 $synonyms = array_values( array_unique( array_merge(
 757                                         $newSynonyms, $oldSynonyms ) ) );
 758                                 $value[$magicName] = array_merge( array( $fallbackInfo[0] ), $synonyms );
 759                         }
 760                 }
 761         }
 762
 763         /**
 764          * Given an array mapping language code to localisation value, such as is
 765          * found in extension *.i18n.php files, iterate through a fallback sequence
 766          * to merge the given data with an existing primary value.
 767          *
 768          * Returns true if any data from the extension array was used, false
 769          * otherwise.
 770          * @param array $codeSequence
 771          * @param string $key
 772          * @param mixed $value
 773          * @param mixed $fallbackValue
 774          * @return bool
 775          */
 776         protected function mergeExtensionItem( $codeSequence, $key, &$value, $fallbackValue ) {
 777                 $used = false;
 778                 foreach ( $codeSequence as $code ) {
 779                         if ( isset( $fallbackValue[$code] ) ) {
 780                                 $this->mergeItem( $key, $value, $fallbackValue[$code] );
 781                                 $used = true;
 782                         }
 783                 }
 784
 785                 return $used;
 786         }
 787
 788         /**
 789          * Gets the combined list of messages dirs from
 790          * core and extensions
 791          *
 792          * @since 1.25
 793          * @return array
 794          */
 795         public function getMessagesDirs() {
 796                 global $wgMessagesDirs, $IP;
 797                 return array(
 798                         'core' => "$IP/languages/i18n",
 799                         'api' => "$IP/includes/api/i18n",
 800                         'oojs-ui' => "$IP/resources/lib/oojs-ui/i18n",
 801                 ) + $wgMessagesDirs;
 802         }
 803
 804         /**
 805          * Load localisation data for a given language for both core and extensions
 806          * and save it to the persistent cache store and the process cache
 807          * @param string $code
 808          * @throws MWException
 809          */
 810         public function recache( $code ) {
 811                 global $wgExtensionMessagesFiles;
 812
 813                 if ( !$code ) {
 814                         throw new MWException( "Invalid language code requested" );
 815                 }
 816                 $this->recachedLangs[$code] = true;
 817
 818                 # Initial values
 819                 $initialData = array_combine(
 820                         self::$allKeys,
 821                         array_fill( 0, count( self::$allKeys ), null ) );
 822                 $coreData = $initialData;
 823                 $deps = array();
 824
 825                 # Load the primary localisation from the source file
 826                 $data = $this->readSourceFilesAndRegisterDeps( $code, $deps );
 827                 if ( $data === false ) {
 828                         wfDebug( __METHOD__ . ": no localisation file for $code, using fallback to en\n" );
 829                         $coreData['fallback'] = 'en';
 830                 } else {
 831                         wfDebug( __METHOD__ . ": got localisation for $code from source\n" );
 832
 833                         # Merge primary localisation
 834                         foreach ( $data as $key => $value ) {
 835                                 $this->mergeItem( $key, $coreData[$key], $value );
 836                         }
 837                 }
 838
 839                 # Fill in the fallback if it's not there already
 840                 if ( is_null( $coreData['fallback'] ) ) {
 841                         $coreData['fallback'] = $code === 'en' ? false : 'en';
 842                 }
 843                 if ( $coreData['fallback'] === false ) {
 844                         $coreData['fallbackSequence'] = array();
 845                 } else {
 846                         $coreData['fallbackSequence'] = array_map( 'trim', explode( ',', $coreData['fallback'] ) );
 847                         $len = count( $coreData['fallbackSequence'] );
 848
 849                         # Ensure that the sequence ends at en
 850                         if ( $coreData['fallbackSequence'][$len - 1] !== 'en' ) {
 851                                 $coreData['fallbackSequence'][] = 'en';
 852                         }
 853                 }
 854
 855                 $codeSequence = array_merge( array( $code ), $coreData['fallbackSequence'] );
 856                 $messageDirs = $this->getMessagesDirs();
 857
 858                 # Load non-JSON localisation data for extensions
 859                 $extensionData = array_combine(
 860                         $codeSequence,
 861                         array_fill( 0, count( $codeSequence ), $initialData ) );
 862                 foreach ( $wgExtensionMessagesFiles as $extension => $fileName ) {
 863                         if ( isset( $messageDirs[$extension] ) ) {
 864                                 # This extension has JSON message data; skip the PHP shim
 865                                 continue;
 866                         }
 867
 868                         $data = $this->readPHPFile( $fileName, 'extension' );
 869                         $used = false;
 870
 871                         foreach ( $data as $key => $item ) {
 872                                 foreach ( $codeSequence as $csCode ) {
 873                                         if ( isset( $item[$csCode] ) ) {
 874                                                 $this->mergeItem( $key, $extensionData[$csCode][$key], $item[$csCode] );
 875                                                 $used = true;
 876                                         }
 877                                 }
 878                         }
 879
 880                         if ( $used ) {
 881                                 $deps[] = new FileDependency( $fileName );
 882                         }
 883                 }
 884
 885                 # Load the localisation data for each fallback, then merge it into the full array
 886                 $allData = $initialData;
 887                 foreach ( $codeSequence as $csCode ) {
 888                         $csData = $initialData;
 889
 890                         # Load core messages and the extension localisations.
 891                         foreach ( $messageDirs as $dirs ) {
 892                                 foreach ( (array)$dirs as $dir ) {
 893                                         $fileName = "$dir/$csCode.json";
 894                                         $data = $this->readJSONFile( $fileName );
 895
 896                                         foreach ( $data as $key => $item ) {
 897                                                 $this->mergeItem( $key, $csData[$key], $item );
 898                                         }
 899
 900                                         $deps[] = new FileDependency( $fileName );
 901                                 }
 902                         }
 903
 904                         # Merge non-JSON extension data
 905                         if ( isset( $extensionData[$csCode] ) ) {
 906                                 foreach ( $extensionData[$csCode] as $key => $item ) {
 907                                         $this->mergeItem( $key, $csData[$key], $item );
 908                                 }
 909                         }
 910
 911                         if ( $csCode === $code ) {
 912                                 # Merge core data into extension data
 913                                 foreach ( $coreData as $key => $item ) {
 914                                         $this->mergeItem( $key, $csData[$key], $item );
 915                                 }
 916                         } else {
 917                                 # Load the secondary localisation from the source file to
 918                                 # avoid infinite cycles on cyclic fallbacks
 919                                 $fbData = $this->readSourceFilesAndRegisterDeps( $csCode, $deps );
 920                                 if ( $fbData !== false ) {
 921                                         # Only merge the keys that make sense to merge
 922                                         foreach ( self::$allKeys as $key ) {
 923                                                 if ( !isset( $fbData[$key] ) ) {
 924                                                         continue;
 925                                                 }
 926
 927                                                 if ( is_null( $coreData[$key] ) || $this->isMergeableKey( $key ) ) {
 928                                                         $this->mergeItem( $key, $csData[$key], $fbData[$key] );
 929                                                 }
 930                                         }
 931                                 }
 932                         }
 933
 934                         # Allow extensions an opportunity to adjust the data for this
 935                         # fallback
 936                         Hooks::run( 'LocalisationCacheRecacheFallback', array( $this, $csCode, &$csData ) );
 937
 938                         # Merge the data for this fallback into the final array
 939                         if ( $csCode === $code ) {
 940                                 $allData = $csData;
 941                         } else {
 942                                 foreach ( self::$allKeys as $key ) {
 943                                         if ( !isset( $csData[$key] ) ) {
 944                                                 continue;
 945                                         }
 946
 947                                         if ( is_null( $allData[$key] ) || $this->isMergeableKey( $key ) ) {
 948                                                 $this->mergeItem( $key, $allData[$key], $csData[$key] );
 949                                         }
 950                                 }
 951                         }
 952                 }
 953
 954                 # Add cache dependencies for any referenced globals
 955                 $deps['wgExtensionMessagesFiles'] = new GlobalDependency( 'wgExtensionMessagesFiles' );
 956                 // $wgMessagesDirs is used in LocalisationCache::getMessagesDirs()
 957                 $deps['wgMessagesDirs'] = new GlobalDependency( 'wgMessagesDirs' );
 958                 $deps['version'] = new ConstantDependency( 'LocalisationCache::VERSION' );
 959
 960                 # Add dependencies to the cache entry
 961                 $allData['deps'] = $deps;
 962
 963                 # Replace spaces with underscores in namespace names
 964                 $allData['namespaceNames'] = str_replace( ' ', '_', $allData['namespaceNames'] );
 965
 966                 # And do the same for special page aliases. $page is an array.
 967                 foreach ( $allData['specialPageAliases'] as &$page ) {
 968                         $page = str_replace( ' ', '_', $page );
 969                 }
 970                 # Decouple the reference to prevent accidental damage
 971                 unset( $page );
 972
 973                 # If there were no plural rules, return an empty array
 974                 if ( $allData['pluralRules'] === null ) {
 975                         $allData['pluralRules'] = array();
 976                 }
 977                 if ( $allData['compiledPluralRules'] === null ) {
 978                         $allData['compiledPluralRules'] = array();
 979                 }
 980                 # If there were no plural rule types, return an empty array
 981                 if ( $allData['pluralRuleTypes'] === null ) {
 982                         $allData['pluralRuleTypes'] = array();
 983                 }
 984
 985                 # Set the list keys
 986                 $allData['list'] = array();
 987                 foreach ( self::$splitKeys as $key ) {
 988                         $allData['list'][$key] = array_keys( $allData[$key] );
 989                 }
 990                 # Run hooks
 991                 $purgeBlobs = true;
 992                 Hooks::run( 'LocalisationCacheRecache', array( $this, $code, &$allData, &$purgeBlobs ) );
 993
 994                 if ( is_null( $allData['namespaceNames'] ) ) {
 995                         throw new MWException( __METHOD__ . ': Localisation data failed sanity check! ' .
 996                                 'Check that your languages/messages/MessagesEn.php file is intact.' );
 997                 }
 998
 999                 # Set the preload key
1000                 $allData['preload'] = $this->buildPreload( $allData );
1001
1002                 # Save to the process cache and register the items loaded
1003                 $this->data[$code] = $allData;
1004                 foreach ( $allData as $key => $item ) {
1005                         $this->loadedItems[$code][$key] = true;
1006                 }
1007
1008                 # Save to the persistent cache
1009                 $this->store->startWrite( $code );
1010                 foreach ( $allData as $key => $value ) {
1011                         if ( in_array( $key, self::$splitKeys ) ) {
1012                                 foreach ( $value as $subkey => $subvalue ) {
1013                                         $this->store->set( "$key:$subkey", $subvalue );
1014                                 }
1015                         } else {
1016                                 $this->store->set( $key, $value );
1017                         }
1018                 }
1019                 $this->store->finishWrite();
1020
1021                 # Clear out the MessageBlobStore
1022                 # HACK: If using a null (i.e. disabled) storage backend, we
1023                 # can't write to the MessageBlobStore either
1024                 if ( $purgeBlobs && !$this->store instanceof LCStoreNull ) {
1025                         $blobStore = new MessageBlobStore();
1026                         $blobStore->clear();
1027                 }
1028
1029         }
1030
1031         /**
1032          * Build the preload item from the given pre-cache data.
1033          *
1034          * The preload item will be loaded automatically, improving performance
1035          * for the commonly-requested items it contains.
1036          * @param array $data
1037          * @return array
1038          */
1039         protected function buildPreload( $data ) {
1040                 $preload = array( 'messages' => array() );
1041                 foreach ( self::$preloadedKeys as $key ) {
1042                         $preload[$key] = $data[$key];
1043                 }
1044
1045                 foreach ( $data['preloadedMessages'] as $subkey ) {
1046                         if ( isset( $data['messages'][$subkey] ) ) {
1047                                 $subitem = $data['messages'][$subkey];
1048                         } else {
1049                                 $subitem = null;
1050                         }
1051                         $preload['messages'][$subkey] = $subitem;
1052                 }
1053
1054                 return $preload;
1055         }
1056
1057         /**
1058          * Unload the data for a given language from the object cache.
1059          * Reduces memory usage.
1060          * @param string $code
1061          */
1062         public function unload( $code ) {
1063                 unset( $this->data[$code] );
1064                 unset( $this->loadedItems[$code] );
1065                 unset( $this->loadedSubitems[$code] );
1066                 unset( $this->initialisedLangs[$code] );
1067                 unset( $this->shallowFallbacks[$code] );
1068
1069                 foreach ( $this->shallowFallbacks as $shallowCode => $fbCode ) {
1070                         if ( $fbCode === $code ) {
1071                                 $this->unload( $shallowCode );
1072                         }
1073                 }
1074         }
1075
1076         /**
1077          * Unload all data
1078          */
1079         public function unloadAll() {
1080                 foreach ( $this->initialisedLangs as $lang => $unused ) {
1081                         $this->unload( $lang );
1082                 }
1083         }
1084
1085         /**
1086          * Disable the storage backend
1087          */
1088         public function disableBackend() {
1089                 $this->store = new LCStoreNull;
1090                 $this->manualRecache = false;
1091         }
1092 }
1093
1094 /**
1095  * Interface for the persistence layer of LocalisationCache.
1096  *
1097  * The persistence layer is two-level hierarchical cache. The first level
1098  * is the language, the second level is the item or subitem.
1099  *
1100  * Since the data for a whole language is rebuilt in one operation, it needs
1101  * to have a fast and atomic method for deleting or replacing all of the
1102  * current data for a given language. The interface reflects this bulk update
1103  * operation. Callers writing to the cache must first call startWrite(), then
1104  * will call set() a couple of thousand times, then will call finishWrite()
1105  * to commit the operation. When finishWrite() is called, the cache is
1106  * expected to delete all data previously stored for that language.
1107  *
1108  * The values stored are PHP variables suitable for serialize(). Implementations
1109  * of LCStore are responsible for serializing and unserializing.
1110  */
1111 interface LCStore {
1112         /**
1113          * Get a value.
1114          * @param string $code Language code
1115          * @param string $key Cache key
1116          */
1117         function get( $code, $key );
1118
1119         /**
1120          * Start a write transaction.
1121          * @param string $code Language code
1122          */
1123         function startWrite( $code );
1124
1125         /**
1126          * Finish a write transaction.
1127          */
1128         function finishWrite();
1129
1130         /**
1131          * Set a key to a given value. startWrite() must be called before this
1132          * is called, and finishWrite() must be called afterwards.
1133          * @param string $key
1134          * @param mixed $value
1135          */
1136         function set( $key, $value );
1137 }
1138
1139 /**
1140  * LCStore implementation which uses the standard DB functions to store data.
1141  * This will work on any MediaWiki installation.
1142  */
1143 class LCStoreDB implements LCStore {
1144         private $currentLang;
1145         private $writesDone = false;
1146
1147         /** @var DatabaseBase */
1148         private $dbw;
1149         /** @var array */
1150         private $batch = array();
1151
1152         private $readOnly = false;
1153
1154         public function get( $code, $key ) {
1155                 if ( $this->writesDone ) {
1156                         $db = wfGetDB( DB_MASTER );
1157                 } else {
1158                         $db = wfGetDB( DB_SLAVE );
1159                 }
1160                 $row = $db->selectRow( 'l10n_cache', array( 'lc_value' ),
1161                         array( 'lc_lang' => $code, 'lc_key' => $key ), __METHOD__ );
1162                 if ( $row ) {
1163                         return unserialize( $db->decodeBlob( $row->lc_value ) );
1164                 } else {
1165                         return null;
1166                 }
1167         }
1168
1169         public function startWrite( $code ) {
1170                 if ( $this->readOnly ) {
1171                         return;
1172                 } elseif ( !$code ) {
1173                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
1174                 }
1175
1176                 $this->dbw = wfGetDB( DB_MASTER );
1177
1178                 $this->currentLang = $code;
1179                 $this->batch = array();
1180         }
1181
1182         public function finishWrite() {
1183                 if ( $this->readOnly ) {
1184                         return;
1185                 } elseif ( is_null( $this->currentLang ) ) {
1186                         throw new MWException( __CLASS__ . ': must call startWrite() before finishWrite()' );
1187                 }
1188
1189                 $this->dbw->begin( __METHOD__ );
1190                 try {
1191                         $this->dbw->delete( 'l10n_cache',
1192                                 array( 'lc_lang' => $this->currentLang ), __METHOD__ );
1193                         foreach ( array_chunk( $this->batch, 500 ) as $rows ) {
1194                                 $this->dbw->insert( 'l10n_cache', $rows, __METHOD__ );
1195                         }
1196                         $this->writesDone = true;
1197                 } catch ( DBQueryError $e ) {
1198                         if ( $this->dbw->wasReadOnlyError() ) {
1199                                 $this->readOnly = true; // just avoid site down time
1200                         } else {
1201                                 throw $e;
1202                         }
1203                 }
1204                 $this->dbw->commit( __METHOD__ );
1205
1206                 $this->currentLang = null;
1207                 $this->batch = array();
1208         }
1209
1210         public function set( $key, $value ) {
1211                 if ( $this->readOnly ) {
1212                         return;
1213                 } elseif ( is_null( $this->currentLang ) ) {
1214                         throw new MWException( __CLASS__ . ': must call startWrite() before set()' );
1215                 }
1216
1217                 $this->batch[] = array(
1218                         'lc_lang' => $this->currentLang,
1219                         'lc_key' => $key,
1220                         'lc_value' => $this->dbw->encodeBlob( serialize( $value ) ) );
1221         }
1222 }
1223
1224 /**
1225  * LCStore implementation which stores data as a collection of CDB files in the
1226  * directory given by $wgCacheDirectory. If $wgCacheDirectory is not set, this
1227  * will throw an exception.
1228  *
1229  * Profiling indicates that on Linux, this implementation outperforms MySQL if
1230  * the directory is on a local filesystem and there is ample kernel cache
1231  * space. The performance advantage is greater when the DBA extension is
1232  * available than it is with the PHP port.
1233  *
1234  * See Cdb.php and http://cr.yp.to/cdb.html
1235  */
1236 class LCStoreCDB implements LCStore {
1237         /** @var CdbReader[] */
1238         private $readers;
1239
1240         /** @var CdbWriter */
1241         private $writer;
1242
1243         /** @var string Current language code */
1244         private $currentLang;
1245
1246         /** @var bool|string Cache directory. False if not set */
1247         private $directory;
1248
1249         function __construct( $conf = array() ) {
1250                 global $wgCacheDirectory;
1251
1252                 if ( isset( $conf['directory'] ) ) {
1253                         $this->directory = $conf['directory'];
1254                 } else {
1255                         $this->directory = $wgCacheDirectory;
1256                 }
1257         }
1258
1259         public function get( $code, $key ) {
1260                 if ( !isset( $this->readers[$code] ) ) {
1261                         $fileName = $this->getFileName( $code );
1262
1263                         $this->readers[$code] = false;
1264                         if ( file_exists( $fileName ) ) {
1265                                 try {
1266                                         $this->readers[$code] = CdbReader::open( $fileName );
1267                                 } catch ( CdbException $e ) {
1268                                         wfDebug( __METHOD__ . ": unable to open cdb file for reading\n" );
1269                                 }
1270                         }
1271                 }
1272
1273                 if ( !$this->readers[$code] ) {
1274                         return null;
1275                 } else {
1276                         $value = false;
1277                         try {
1278                                 $value = $this->readers[$code]->get( $key );
1279                         } catch ( CdbException $e ) {
1280                                 wfDebug( __METHOD__ . ": CdbException caught, error message was "
1281                                         . $e->getMessage() . "\n" );
1282                         }
1283                         if ( $value === false ) {
1284                                 return null;
1285                         }
1286
1287                         return unserialize( $value );
1288                 }
1289         }
1290
1291         public function startWrite( $code ) {
1292                 if ( !file_exists( $this->directory ) ) {
1293                         if ( !wfMkdirParents( $this->directory, null, __METHOD__ ) ) {
1294                                 throw new MWException( "Unable to create the localisation store " .
1295                                         "directory \"{$this->directory}\"" );
1296                         }
1297                 }
1298
1299                 // Close reader to stop permission errors on write
1300                 if ( !empty( $this->readers[$code] ) ) {
1301                         $this->readers[$code]->close();
1302                 }
1303
1304                 try {
1305                         $this->writer = CdbWriter::open( $this->getFileName( $code ) );
1306                 } catch ( CdbException $e ) {
1307                         throw new MWException( $e->getMessage() );
1308                 }
1309                 $this->currentLang = $code;
1310         }
1311
1312         public function finishWrite() {
1313                 // Close the writer
1314                 try {
1315                         $this->writer->close();
1316                 } catch ( CdbException $e ) {
1317                         throw new MWException( $e->getMessage() );
1318                 }
1319                 $this->writer = null;
1320                 unset( $this->readers[$this->currentLang] );
1321                 $this->currentLang = null;
1322         }
1323
1324         public function set( $key, $value ) {
1325                 if ( is_null( $this->writer ) ) {
1326                         throw new MWException( __CLASS__ . ': must call startWrite() before calling set()' );
1327                 }
1328                 try {
1329                         $this->writer->set( $key, serialize( $value ) );
1330                 } catch ( CdbException $e ) {
1331                         throw new MWException( $e->getMessage() );
1332                 }
1333         }
1334
1335         protected function getFileName( $code ) {
1336                 if ( strval( $code ) === '' || strpos( $code, '/' ) !== false ) {
1337                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
1338                 }
1339
1340                 return "{$this->directory}/l10n_cache-$code.cdb";
1341         }
1342 }
1343
1344 /**
1345  * Null store backend, used to avoid DB errors during install
1346  */
1347 class LCStoreNull implements LCStore {
1348         public function get( $code, $key ) {
1349                 return null;
1350         }
1351
1352         public function startWrite( $code ) {
1353         }
1354
1355         public function finishWrite() {
1356         }
1357
1358         public function set( $key, $value ) {
1359         }
1360 }
1361
1362 /**
1363  * A localisation cache optimised for loading large amounts of data for many
1364  * languages. Used by rebuildLocalisationCache.php.
1365  */
1366 class LocalisationCacheBulkLoad extends LocalisationCache {
1367         /**
1368          * A cache of the contents of data files.
1369          * Core files are serialized to avoid using ~1GB of RAM during a recache.
1370          */
1371         private $fileCache = array();
1372
1373         /**
1374          * Most recently used languages. Uses the linked-list aspect of PHP hashtables
1375          * to keep the most recently used language codes at the end of the array, and
1376          * the language codes that are ready to be deleted at the beginning.
1377          */
1378         private $mruLangs = array();
1379
1380         /**
1381          * Maximum number of languages that may be loaded into $this->data
1382          */
1383         private $maxLoadedLangs = 10;
1384
1385         /**
1386          * @param string $fileName
1387          * @param string $fileType
1388          * @return array|mixed
1389          */
1390         protected function readPHPFile( $fileName, $fileType ) {
1391                 $serialize = $fileType === 'core';
1392                 if ( !isset( $this->fileCache[$fileName][$fileType] ) ) {
1393                         $data = parent::readPHPFile( $fileName, $fileType );
1394
1395                         if ( $serialize ) {
1396                                 $encData = serialize( $data );
1397                         } else {
1398                                 $encData = $data;
1399                         }
1400
1401                         $this->fileCache[$fileName][$fileType] = $encData;
1402
1403                         return $data;
1404                 } elseif ( $serialize ) {
1405                         return unserialize( $this->fileCache[$fileName][$fileType] );
1406                 } else {
1407                         return $this->fileCache[$fileName][$fileType];
1408                 }
1409         }
1410
1411         /**
1412          * @param string $code
1413          * @param string $key
1414          * @return mixed
1415          */
1416         public function getItem( $code, $key ) {
1417                 unset( $this->mruLangs[$code] );
1418                 $this->mruLangs[$code] = true;
1419
1420                 return parent::getItem( $code, $key );
1421         }
1422
1423         /**
1424          * @param string $code
1425          * @param string $key
1426          * @param string $subkey
1427          * @return mixed
1428          */
1429         public function getSubitem( $code, $key, $subkey ) {
1430                 unset( $this->mruLangs[$code] );
1431                 $this->mruLangs[$code] = true;
1432
1433                 return parent::getSubitem( $code, $key, $subkey );
1434         }
1435
1436         /**
1437          * @param string $code
1438          */
1439         public function recache( $code ) {
1440                 parent::recache( $code );
1441                 unset( $this->mruLangs[$code] );
1442                 $this->mruLangs[$code] = true;
1443                 $this->trimCache();
1444         }
1445
1446         /**
1447          * @param string $code
1448          */
1449         public function unload( $code ) {
1450                 unset( $this->mruLangs[$code] );
1451                 parent::unload( $code );
1452         }
1453
1454         /**
1455          * Unload cached languages until there are less than $this->maxLoadedLangs
1456          */
1457         protected function trimCache() {
1458                 while ( count( $this->data ) > $this->maxLoadedLangs && count( $this->mruLangs ) ) {
1459                         reset( $this->mruLangs );
1460                         $code = key( $this->mruLangs );
1461                         wfDebug( __METHOD__ . ": unloading $code\n" );
1462                         $this->unload( $code );
1463                 }
1464         }
1465 }