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 define( 'MW_LC_VERSION', 2 );
  24
  25 /**
  26  * Class for caching the contents of localisation files, Messages*.php
  27  * and *.i18n.php.
  28  *
  29  * An instance of this class is available using Language::getLocalisationCache().
  30  *
  31  * The values retrieved from here are merged, containing items from extension
  32  * files, core messages files and the language fallback sequence (e.g. zh-cn ->
  33  * zh-hans -> en ). Some common errors are corrected, for example namespace
  34  * names with spaces instead of underscores, but heavyweight processing, such
  35  * as grammatical transformation, is done by the caller.
  36  */
  37 class LocalisationCache {
  38         /** Configuration associative array */
  39         private $conf;
  40
  41         /**
  42          * True if recaching should only be done on an explicit call to recache().
  43          * Setting this reduces the overhead of cache freshness checking, which
  44          * requires doing a stat() for every extension i18n file.
  45          */
  46         private $manualRecache = false;
  47
  48         /**
  49          * True to treat all files as expired until they are regenerated by this object.
  50          */
  51         private $forceRecache = false;
  52
  53         /**
  54          * The cache data. 3-d array, where the first key is the language code,
  55          * the second key is the item key e.g. 'messages', and the third key is
  56          * an item specific subkey index. Some items are not arrays and so for those
  57          * items, there are no subkeys.
  58          */
  59         protected $data = array();
  60
  61         /**
  62          * The persistent store object. An instance of LCStore.
  63          *
  64          * @var LCStore
  65          */
  66         private $store;
  67
  68         /**
  69          * A 2-d associative array, code/key, where presence indicates that the item
  70          * is loaded. Value arbitrary.
  71          *
  72          * For split items, if set, this indicates that all of the subitems have been
  73          * loaded.
  74          */
  75         private $loadedItems = array();
  76
  77         /**
  78          * A 3-d associative array, code/key/subkey, where presence indicates that
  79          * the subitem is loaded. Only used for the split items, i.e. messages.
  80          */
  81         private $loadedSubitems = array();
  82
  83         /**
  84          * An array where presence of a key indicates that that language has been
  85          * initialised. Initialisation includes checking for cache expiry and doing
  86          * any necessary updates.
  87          */
  88         private $initialisedLangs = array();
  89
  90         /**
  91          * An array mapping non-existent pseudo-languages to fallback languages. This
  92          * is filled by initShallowFallback() when data is requested from a language
  93          * that lacks a Messages*.php file.
  94          */
  95         private $shallowFallbacks = array();
  96
  97         /**
  98          * An array where the keys are codes that have been recached by this instance.
  99          */
 100         private $recachedLangs = array();
 101
 102         /**
 103          * All item keys
 104          */
 105         static public $allKeys = array(
 106                 'fallback', 'namespaceNames', 'bookstoreList',
 107                 'magicWords', 'messages', 'rtl', 'capitalizeAllNouns', 'digitTransformTable',
 108                 'separatorTransformTable', 'fallback8bitEncoding', 'linkPrefixExtension',
 109                 'linkTrail', 'linkPrefixCharset', 'namespaceAliases',
 110                 'dateFormats', 'datePreferences', 'datePreferenceMigrationMap',
 111                 'defaultDateFormat', 'extraUserToggles', 'specialPageAliases',
 112                 'imageFiles', 'preloadedMessages', 'namespaceGenderAliases',
 113                 'digitGroupingPattern', 'pluralRules', 'pluralRuleTypes', 'compiledPluralRules',
 114         );
 115
 116         /**
 117          * Keys for items which consist of associative arrays, which may be merged
 118          * by a fallback sequence.
 119          */
 120         static public $mergeableMapKeys = array( 'messages', 'namespaceNames',
 121                 'dateFormats', 'imageFiles', 'preloadedMessages'
 122         );
 123
 124         /**
 125          * Keys for items which are a numbered array.
 126          */
 127         static public $mergeableListKeys = array( 'extraUserToggles' );
 128
 129         /**
 130          * Keys for items which contain an array of arrays of equivalent aliases
 131          * for each subitem. The aliases may be merged by a fallback sequence.
 132          */
 133         static public $mergeableAliasListKeys = array( 'specialPageAliases' );
 134
 135         /**
 136          * Keys for items which contain an associative array, and may be merged if
 137          * the primary value contains the special array key "inherit". That array
 138          * key is removed after the first merge.
 139          */
 140         static public $optionalMergeKeys = array( 'bookstoreList' );
 141
 142         /**
 143          * Keys for items that are formatted like $magicWords
 144          */
 145         static public $magicWordKeys = array( 'magicWords' );
 146
 147         /**
 148          * Keys for items where the subitems are stored in the backend separately.
 149          */
 150         static public $splitKeys = array( 'messages' );
 151
 152         /**
 153          * Keys which are loaded automatically by initLanguage()
 154          */
 155         static public $preloadedKeys = array( 'dateFormats', 'namespaceNames' );
 156
 157         /**
 158          * Associative array of cached plural rules. The key is the language code,
 159          * the value is an array of plural rules for that language.
 160          */
 161         private $pluralRules = null;
 162
 163         /**
 164          * Associative array of cached plural rule types. The key is the language
 165          * code, the value is an array of plural rule types for that language. For
 166          * example, $pluralRuleTypes['ar'] = ['zero', 'one', 'two', 'few', 'many'].
 167          * The index for each rule type matches the index for the rule in
 168          * $pluralRules, thus allowing correlation between the two. The reason we
 169          * don't just use the type names as the keys in $pluralRules is because
 170          * Language::convertPlural applies the rules based on numeric order (or
 171          * explicit numeric parameter), not based on the name of the rule type. For
 172          * example, {{plural:count|wordform1|wordform2|wordform3}}, rather than
 173          * {{plural:count|one=wordform1|two=wordform2|many=wordform3}}.
 174          */
 175         private $pluralRuleTypes = null;
 176
 177         private $mergeableKeys = null;
 178
 179         /**
 180          * Constructor.
 181          * For constructor parameters, see the documentation in DefaultSettings.php
 182          * for $wgLocalisationCacheConf.
 183          *
 184          * @param $conf Array
 185          * @throws MWException
 186          */
 187         function __construct( $conf ) {
 188                 global $wgCacheDirectory;
 189
 190                 $this->conf = $conf;
 191                 $storeConf = array();
 192                 if ( !empty( $conf['storeClass'] ) ) {
 193                         $storeClass = $conf['storeClass'];
 194                 } else {
 195                         switch ( $conf['store'] ) {
 196                                 case 'files':
 197                                 case 'file':
 198                                         $storeClass = 'LCStoreCDB';
 199                                         break;
 200                                 case 'db':
 201                                         $storeClass = 'LCStoreDB';
 202                                         break;
 203                                 case 'accel':
 204                                         $storeClass = 'LCStoreAccel';
 205                                         break;
 206                                 case 'detect':
 207                                         $storeClass = $wgCacheDirectory ? 'LCStoreCDB' : 'LCStoreDB';
 208                                         break;
 209                                 default:
 210                                         throw new MWException(
 211                                                 'Please set $wgLocalisationCacheConf[\'store\'] to something sensible.' );
 212                         }
 213                 }
 214
 215                 wfDebug( get_class( $this ) . ": using store $storeClass\n" );
 216                 if ( !empty( $conf['storeDirectory'] ) ) {
 217                         $storeConf['directory'] = $conf['storeDirectory'];
 218                 }
 219
 220                 $this->store = new $storeClass( $storeConf );
 221                 foreach ( array( 'manualRecache', 'forceRecache' ) as $var ) {
 222                         if ( isset( $conf[$var] ) ) {
 223                                 $this->$var = $conf[$var];
 224                         }
 225                 }
 226         }
 227
 228         /**
 229          * Returns true if the given key is mergeable, that is, if it is an associative
 230          * array which can be merged through a fallback sequence.
 231          * @param $key
 232          * @return bool
 233          */
 234         public function isMergeableKey( $key ) {
 235                 if ( $this->mergeableKeys === null ) {
 236                         $this->mergeableKeys = array_flip( array_merge(
 237                                 self::$mergeableMapKeys,
 238                                 self::$mergeableListKeys,
 239                                 self::$mergeableAliasListKeys,
 240                                 self::$optionalMergeKeys,
 241                                 self::$magicWordKeys
 242                         ) );
 243                 }
 244
 245                 return isset( $this->mergeableKeys[$key] );
 246         }
 247
 248         /**
 249          * Get a cache item.
 250          *
 251          * Warning: this may be slow for split items (messages), since it will
 252          * need to fetch all of the subitems from the cache individually.
 253          * @param $code
 254          * @param $key
 255          * @return mixed
 256          */
 257         public function getItem( $code, $key ) {
 258                 if ( !isset( $this->loadedItems[$code][$key] ) ) {
 259                         wfProfileIn( __METHOD__ . '-load' );
 260                         $this->loadItem( $code, $key );
 261                         wfProfileOut( __METHOD__ . '-load' );
 262                 }
 263
 264                 if ( $key === 'fallback' && isset( $this->shallowFallbacks[$code] ) ) {
 265                         return $this->shallowFallbacks[$code];
 266                 }
 267
 268                 return $this->data[$code][$key];
 269         }
 270
 271         /**
 272          * Get a subitem, for instance a single message for a given language.
 273          * @param $code
 274          * @param $key
 275          * @param $subkey
 276          * @return null
 277          */
 278         public function getSubitem( $code, $key, $subkey ) {
 279                 if ( !isset( $this->loadedSubitems[$code][$key][$subkey] ) &&
 280                         !isset( $this->loadedItems[$code][$key] )
 281                 ) {
 282                         wfProfileIn( __METHOD__ . '-load' );
 283                         $this->loadSubitem( $code, $key, $subkey );
 284                         wfProfileOut( __METHOD__ . '-load' );
 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 $code
 303          * @param $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 $code
 322          * @param $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 $code
 358          * @param $key
 359          * @param $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, at least in LCStoreAccel
 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 $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 ( file_exists( Language::getMessagesFileName( $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 $primaryCode
 494          * @param $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 $_fileName
 506          * @param $_fileType
 507          * @throws MWException
 508          * @return array
 509          */
 510         protected function readPHPFile( $_fileName, $_fileType ) {
 511                 wfProfileIn( __METHOD__ );
 512                 // Disable APC caching
 513                 wfSuppressWarnings();
 514                 $_apcEnabled = ini_set( 'apc.cache_by_default', '0' );
 515                 wfRestoreWarnings();
 516
 517                 include $_fileName;
 518
 519                 wfSuppressWarnings();
 520                 ini_set( 'apc.cache_by_default', $_apcEnabled );
 521                 wfRestoreWarnings();
 522
 523                 if ( $_fileType == 'core' || $_fileType == 'extension' ) {
 524                         $data = compact( self::$allKeys );
 525                 } elseif ( $_fileType == 'aliases' ) {
 526                         $data = compact( 'aliases' );
 527                 } else {
 528                         wfProfileOut( __METHOD__ );
 529                         throw new MWException( __METHOD__ . ": Invalid file type: $_fileType" );
 530                 }
 531                 wfProfileOut( __METHOD__ );
 532
 533                 return $data;
 534         }
 535
 536         /**
 537          * Read a JSON file containing localisation messages.
 538          * @param string $fileName Name of file to read
 539          * @throws MWException if there is a syntax error in the JSON file
 540          * @return array with a 'messages' key, or empty array if the file doesn't exist
 541          */
 542         protected function readJSONFile( $fileName ) {
 543                 wfProfileIn( __METHOD__ );
 544
 545                 if ( !is_readable( $fileName ) ) {
 546                         wfProfileOut( __METHOD__ );
 547
 548                         return array();
 549                 }
 550
 551                 $json = file_get_contents( $fileName );
 552                 if ( $json === false ) {
 553                         wfProfileOut( __METHOD__ );
 554
 555                         return array();
 556                 }
 557
 558                 $data = FormatJson::decode( $json, true );
 559                 if ( $data === null ) {
 560                         wfProfileOut( __METHOD__ );
 561
 562                         throw new MWException( __METHOD__ . ": Invalid JSON file: $fileName" );
 563                 }
 564
 565                 // Remove keys starting with '@', they're reserved for metadata and non-message data
 566                 foreach ( $data as $key => $unused ) {
 567                         if ( $key === '' || $key[0] === '@' ) {
 568                                 unset( $data[$key] );
 569                         }
 570                 }
 571
 572                 wfProfileOut( __METHOD__ );
 573
 574                 // The JSON format only supports messages, none of the other variables, so wrap the data
 575                 return array( 'messages' => $data );
 576         }
 577
 578         /**
 579          * Get the compiled plural rules for a given language from the XML files.
 580          * @since 1.20
 581          */
 582         public function getCompiledPluralRules( $code ) {
 583                 $rules = $this->getPluralRules( $code );
 584                 if ( $rules === null ) {
 585                         return null;
 586                 }
 587                 try {
 588                         $compiledRules = CLDRPluralRuleEvaluator::compile( $rules );
 589                 } catch ( CLDRPluralRuleError $e ) {
 590                         wfDebugLog( 'l10n', $e->getMessage() );
 591
 592                         return array();
 593                 }
 594
 595                 return $compiledRules;
 596         }
 597
 598         /**
 599          * Get the plural rules for a given language from the XML files.
 600          * Cached.
 601          * @since 1.20
 602          */
 603         public function getPluralRules( $code ) {
 604                 if ( $this->pluralRules === null ) {
 605                         $this->loadPluralFiles();
 606                 }
 607                 if ( !isset( $this->pluralRules[$code] ) ) {
 608                         return null;
 609                 } else {
 610                         return $this->pluralRules[$code];
 611                 }
 612         }
 613
 614         /**
 615          * Get the plural rule types for a given language from the XML files.
 616          * Cached.
 617          * @since 1.22
 618          */
 619         public function getPluralRuleTypes( $code ) {
 620                 if ( $this->pluralRuleTypes === null ) {
 621                         $this->loadPluralFiles();
 622                 }
 623                 if ( !isset( $this->pluralRuleTypes[$code] ) ) {
 624                         return null;
 625                 } else {
 626                         return $this->pluralRuleTypes[$code];
 627                 }
 628         }
 629
 630         /**
 631          * Load the plural XML files.
 632          */
 633         protected function loadPluralFiles() {
 634                 global $IP;
 635                 $cldrPlural = "$IP/languages/data/plurals.xml";
 636                 $mwPlural = "$IP/languages/data/plurals-mediawiki.xml";
 637                 // Load CLDR plural rules
 638                 $this->loadPluralFile( $cldrPlural );
 639                 if ( file_exists( $mwPlural ) ) {
 640                         // Override or extend
 641                         $this->loadPluralFile( $mwPlural );
 642                 }
 643         }
 644
 645         /**
 646          * Load a plural XML file with the given filename, compile the relevant
 647          * rules, and save the compiled rules in a process-local cache.
 648          */
 649         protected function loadPluralFile( $fileName ) {
 650                 $doc = new DOMDocument;
 651                 $doc->load( $fileName );
 652                 $rulesets = $doc->getElementsByTagName( "pluralRules" );
 653                 foreach ( $rulesets as $ruleset ) {
 654                         $codes = $ruleset->getAttribute( 'locales' );
 655                         $rules = array();
 656                         $ruleTypes = array();
 657                         $ruleElements = $ruleset->getElementsByTagName( "pluralRule" );
 658                         foreach ( $ruleElements as $elt ) {
 659                                 $ruleType = $elt->getAttribute( 'count' );
 660                                 if ( $ruleType === 'other' ) {
 661                                         // Don't record "other" rules, which have an empty condition
 662                                         continue;
 663                                 }
 664                                 $rules[] = $elt->nodeValue;
 665                                 $ruleTypes[] = $ruleType;
 666                         }
 667                         foreach ( explode( ' ', $codes ) as $code ) {
 668                                 $this->pluralRules[$code] = $rules;
 669                                 $this->pluralRuleTypes[$code] = $ruleTypes;
 670                         }
 671                 }
 672         }
 673
 674         /**
 675          * Read the data from the source files for a given language, and register
 676          * the relevant dependencies in the $deps array. If the localisation
 677          * exists, the data array is returned, otherwise false is returned.
 678          */
 679         protected function readSourceFilesAndRegisterDeps( $code, &$deps ) {
 680                 global $IP;
 681                 wfProfileIn( __METHOD__ );
 682
 683                 $fileName = Language::getMessagesFileName( $code );
 684                 if ( !file_exists( $fileName ) ) {
 685                         wfProfileOut( __METHOD__ );
 686
 687                         return false;
 688                 }
 689
 690                 $deps[] = new FileDependency( $fileName );
 691                 $data = $this->readPHPFile( $fileName, 'core' );
 692
 693                 # Load CLDR plural rules for JavaScript
 694                 $data['pluralRules'] = $this->getPluralRules( $code );
 695                 # And for PHP
 696                 $data['compiledPluralRules'] = $this->getCompiledPluralRules( $code );
 697                 # Load plural rule types
 698                 $data['pluralRuleTypes'] = $this->getPluralRuleTypes( $code );
 699
 700                 $deps['plurals'] = new FileDependency( "$IP/languages/data/plurals.xml" );
 701                 $deps['plurals-mw'] = new FileDependency( "$IP/languages/data/plurals-mediawiki.xml" );
 702
 703                 wfProfileOut( __METHOD__ );
 704
 705                 return $data;
 706         }
 707
 708         /**
 709          * Merge two localisation values, a primary and a fallback, overwriting the
 710          * primary value in place.
 711          * @param $key
 712          * @param $value
 713          * @param $fallbackValue
 714          */
 715         protected function mergeItem( $key, &$value, $fallbackValue ) {
 716                 if ( !is_null( $value ) ) {
 717                         if ( !is_null( $fallbackValue ) ) {
 718                                 if ( in_array( $key, self::$mergeableMapKeys ) ) {
 719                                         $value = $value + $fallbackValue;
 720                                 } elseif ( in_array( $key, self::$mergeableListKeys ) ) {
 721                                         $value = array_unique( array_merge( $fallbackValue, $value ) );
 722                                 } elseif ( in_array( $key, self::$mergeableAliasListKeys ) ) {
 723                                         $value = array_merge_recursive( $value, $fallbackValue );
 724                                 } elseif ( in_array( $key, self::$optionalMergeKeys ) ) {
 725                                         if ( !empty( $value['inherit'] ) ) {
 726                                                 $value = array_merge( $fallbackValue, $value );
 727                                         }
 728
 729                                         if ( isset( $value['inherit'] ) ) {
 730                                                 unset( $value['inherit'] );
 731                                         }
 732                                 } elseif ( in_array( $key, self::$magicWordKeys ) ) {
 733                                         $this->mergeMagicWords( $value, $fallbackValue );
 734                                 }
 735                         }
 736                 } else {
 737                         $value = $fallbackValue;
 738                 }
 739         }
 740
 741         /**
 742          * @param $value
 743          * @param $fallbackValue
 744          */
 745         protected function mergeMagicWords( &$value, $fallbackValue ) {
 746                 foreach ( $fallbackValue as $magicName => $fallbackInfo ) {
 747                         if ( !isset( $value[$magicName] ) ) {
 748                                 $value[$magicName] = $fallbackInfo;
 749                         } else {
 750                                 $oldSynonyms = array_slice( $fallbackInfo, 1 );
 751                                 $newSynonyms = array_slice( $value[$magicName], 1 );
 752                                 $synonyms = array_values( array_unique( array_merge(
 753                                         $newSynonyms, $oldSynonyms ) ) );
 754                                 $value[$magicName] = array_merge( array( $fallbackInfo[0] ), $synonyms );
 755                         }
 756                 }
 757         }
 758
 759         /**
 760          * Given an array mapping language code to localisation value, such as is
 761          * found in extension *.i18n.php files, iterate through a fallback sequence
 762          * to merge the given data with an existing primary value.
 763          *
 764          * Returns true if any data from the extension array was used, false
 765          * otherwise.
 766          * @param $codeSequence
 767          * @param $key
 768          * @param $value
 769          * @param $fallbackValue
 770          * @return bool
 771          */
 772         protected function mergeExtensionItem( $codeSequence, $key, &$value, $fallbackValue ) {
 773                 $used = false;
 774                 foreach ( $codeSequence as $code ) {
 775                         if ( isset( $fallbackValue[$code] ) ) {
 776                                 $this->mergeItem( $key, $value, $fallbackValue[$code] );
 777                                 $used = true;
 778                         }
 779                 }
 780
 781                 return $used;
 782         }
 783
 784         /**
 785          * Load localisation data for a given language for both core and extensions
 786          * and save it to the persistent cache store and the process cache
 787          * @param $code
 788          * @throws MWException
 789          */
 790         public function recache( $code ) {
 791                 global $wgExtensionMessagesFiles, $wgMessagesDirs;
 792                 wfProfileIn( __METHOD__ );
 793
 794                 if ( !$code ) {
 795                         wfProfileOut( __METHOD__ );
 796                         throw new MWException( "Invalid language code requested" );
 797                 }
 798                 $this->recachedLangs[$code] = true;
 799
 800                 # Initial values
 801                 $initialData = array_combine(
 802                         self::$allKeys,
 803                         array_fill( 0, count( self::$allKeys ), null ) );
 804                 $coreData = $initialData;
 805                 $deps = array();
 806
 807                 # Load the primary localisation from the source file
 808                 $data = $this->readSourceFilesAndRegisterDeps( $code, $deps );
 809                 if ( $data === false ) {
 810                         wfDebug( __METHOD__ . ": no localisation file for $code, using fallback to en\n" );
 811                         $coreData['fallback'] = 'en';
 812                 } else {
 813                         wfDebug( __METHOD__ . ": got localisation for $code from source\n" );
 814
 815                         # Merge primary localisation
 816                         foreach ( $data as $key => $value ) {
 817                                 $this->mergeItem( $key, $coreData[$key], $value );
 818                         }
 819                 }
 820
 821                 # Fill in the fallback if it's not there already
 822                 if ( is_null( $coreData['fallback'] ) ) {
 823                         $coreData['fallback'] = $code === 'en' ? false : 'en';
 824                 }
 825                 if ( $coreData['fallback'] === false ) {
 826                         $coreData['fallbackSequence'] = array();
 827                 } else {
 828                         $coreData['fallbackSequence'] = array_map( 'trim', explode( ',', $coreData['fallback'] ) );
 829                         $len = count( $coreData['fallbackSequence'] );
 830
 831                         # Ensure that the sequence ends at en
 832                         if ( $coreData['fallbackSequence'][$len - 1] !== 'en' ) {
 833                                 $coreData['fallbackSequence'][] = 'en';
 834                         }
 835
 836                         # Load the fallback localisation item by item and merge it
 837                         foreach ( $coreData['fallbackSequence'] as $fbCode ) {
 838                                 # Load the secondary localisation from the source file to
 839                                 # avoid infinite cycles on cyclic fallbacks
 840                                 $fbData = $this->readSourceFilesAndRegisterDeps( $fbCode, $deps );
 841                                 if ( $fbData === false ) {
 842                                         continue;
 843                                 }
 844
 845                                 foreach ( self::$allKeys as $key ) {
 846                                         if ( !isset( $fbData[$key] ) ) {
 847                                                 continue;
 848                                         }
 849
 850                                         if ( is_null( $coreData[$key] ) || $this->isMergeableKey( $key ) ) {
 851                                                 $this->mergeItem( $key, $coreData[$key], $fbData[$key] );
 852                                         }
 853                                 }
 854                         }
 855                 }
 856
 857                 $codeSequence = array_merge( array( $code ), $coreData['fallbackSequence'] );
 858
 859                 # Load the extension localisations
 860                 # This is done after the core because we know the fallback sequence now.
 861                 # But it has a higher precedence for merging so that we can support things
 862                 # like site-specific message overrides.
 863                 wfProfileIn( __METHOD__ . '-extensions' );
 864                 $allData = $initialData;
 865                 foreach ( $wgMessagesDirs as $dirs ) {
 866                         foreach ( (array)$dirs as $dir ) {
 867                                 foreach ( $codeSequence as $csCode ) {
 868                                         $fileName = "$dir/$csCode.json";
 869                                         $data = $this->readJSONFile( $fileName );
 870
 871                                         foreach ( $data as $key => $item ) {
 872                                                 $this->mergeItem( $key, $allData[$key], $item );
 873                                         }
 874
 875                                         $deps[] = new FileDependency( $fileName );
 876                                 }
 877                         }
 878                 }
 879
 880                 foreach ( $wgExtensionMessagesFiles as $extension => $fileName ) {
 881                         $data = $this->readPHPFile( $fileName, 'extension' );
 882                         $used = false;
 883
 884                         foreach ( $data as $key => $item ) {
 885                                 if ( $key === 'messages' && isset( $wgMessagesDirs[$extension] ) ) {
 886                                         # For backwards compatibility, ignore messages from extensions in
 887                                         # $wgExtensionMessagesFiles that are also present in $wgMessagesDirs.
 888                                         # This allows extensions to use both and be backwards compatible.
 889                                         # Variables other than $messages still need to be supported though.
 890                                         continue;
 891                                 }
 892                                 if ( $this->mergeExtensionItem( $codeSequence, $key, $allData[$key], $item ) ) {
 893                                         $used = true;
 894                                 }
 895                         }
 896
 897                         if ( $used ) {
 898                                 $deps[] = new FileDependency( $fileName );
 899                         }
 900                 }
 901
 902                 # Merge core data into extension data
 903                 foreach ( $coreData as $key => $item ) {
 904                         $this->mergeItem( $key, $allData[$key], $item );
 905                 }
 906                 wfProfileOut( __METHOD__ . '-extensions' );
 907
 908                 # Add cache dependencies for any referenced globals
 909                 $deps['wgExtensionMessagesFiles'] = new GlobalDependency( 'wgExtensionMessagesFiles' );
 910                 $deps['wgMessagesDirs'] = new GlobalDependency( 'wgMessagesDirs' );
 911                 $deps['version'] = new ConstantDependency( 'MW_LC_VERSION' );
 912
 913                 # Add dependencies to the cache entry
 914                 $allData['deps'] = $deps;
 915
 916                 # Replace spaces with underscores in namespace names
 917                 $allData['namespaceNames'] = str_replace( ' ', '_', $allData['namespaceNames'] );
 918
 919                 # And do the same for special page aliases. $page is an array.
 920                 foreach ( $allData['specialPageAliases'] as &$page ) {
 921                         $page = str_replace( ' ', '_', $page );
 922                 }
 923                 # Decouple the reference to prevent accidental damage
 924                 unset( $page );
 925
 926                 # If there were no plural rules, return an empty array
 927                 if ( $allData['pluralRules'] === null ) {
 928                         $allData['pluralRules'] = array();
 929                 }
 930                 if ( $allData['compiledPluralRules'] === null ) {
 931                         $allData['compiledPluralRules'] = array();
 932                 }
 933                 # If there were no plural rule types, return an empty array
 934                 if ( $allData['pluralRuleTypes'] === null ) {
 935                         $allData['pluralRuleTypes'] = array();
 936                 }
 937
 938                 # Set the list keys
 939                 $allData['list'] = array();
 940                 foreach ( self::$splitKeys as $key ) {
 941                         $allData['list'][$key] = array_keys( $allData[$key] );
 942                 }
 943                 # Run hooks
 944                 $purgeBlobs = true;
 945                 wfRunHooks( 'LocalisationCacheRecache', array( $this, $code, &$allData, &$purgeBlobs ) );
 946
 947                 if ( is_null( $allData['namespaceNames'] ) ) {
 948                         wfProfileOut( __METHOD__ );
 949                         throw new MWException( __METHOD__ . ': Localisation data failed sanity check! ' .
 950                                 'Check that your languages/messages/MessagesEn.php file is intact.' );
 951                 }
 952
 953                 # Set the preload key
 954                 $allData['preload'] = $this->buildPreload( $allData );
 955
 956                 # Save to the process cache and register the items loaded
 957                 $this->data[$code] = $allData;
 958                 foreach ( $allData as $key => $item ) {
 959                         $this->loadedItems[$code][$key] = true;
 960                 }
 961
 962                 # Save to the persistent cache
 963                 wfProfileIn( __METHOD__ . '-write' );
 964                 $this->store->startWrite( $code );
 965                 foreach ( $allData as $key => $value ) {
 966                         if ( in_array( $key, self::$splitKeys ) ) {
 967                                 foreach ( $value as $subkey => $subvalue ) {
 968                                         $this->store->set( "$key:$subkey", $subvalue );
 969                                 }
 970                         } else {
 971                                 $this->store->set( $key, $value );
 972                         }
 973                 }
 974                 $this->store->finishWrite();
 975                 wfProfileOut( __METHOD__ . '-write' );
 976
 977                 # Clear out the MessageBlobStore
 978                 # HACK: If using a null (i.e. disabled) storage backend, we
 979                 # can't write to the MessageBlobStore either
 980                 if ( $purgeBlobs && !$this->store instanceof LCStoreNull ) {
 981                         MessageBlobStore::clear();
 982                 }
 983
 984                 wfProfileOut( __METHOD__ );
 985         }
 986
 987         /**
 988          * Build the preload item from the given pre-cache data.
 989          *
 990          * The preload item will be loaded automatically, improving performance
 991          * for the commonly-requested items it contains.
 992          * @param $data
 993          * @return array
 994          */
 995         protected function buildPreload( $data ) {
 996                 $preload = array( 'messages' => array() );
 997                 foreach ( self::$preloadedKeys as $key ) {
 998                         $preload[$key] = $data[$key];
 999                 }
1000
1001                 foreach ( $data['preloadedMessages'] as $subkey ) {
1002                         if ( isset( $data['messages'][$subkey] ) ) {
1003                                 $subitem = $data['messages'][$subkey];
1004                         } else {
1005                                 $subitem = null;
1006                         }
1007                         $preload['messages'][$subkey] = $subitem;
1008                 }
1009
1010                 return $preload;
1011         }
1012
1013         /**
1014          * Unload the data for a given language from the object cache.
1015          * Reduces memory usage.
1016          * @param $code
1017          */
1018         public function unload( $code ) {
1019                 unset( $this->data[$code] );
1020                 unset( $this->loadedItems[$code] );
1021                 unset( $this->loadedSubitems[$code] );
1022                 unset( $this->initialisedLangs[$code] );
1023                 unset( $this->shallowFallbacks[$code] );
1024
1025                 foreach ( $this->shallowFallbacks as $shallowCode => $fbCode ) {
1026                         if ( $fbCode === $code ) {
1027                                 $this->unload( $shallowCode );
1028                         }
1029                 }
1030         }
1031
1032         /**
1033          * Unload all data
1034          */
1035         public function unloadAll() {
1036                 foreach ( $this->initialisedLangs as $lang => $unused ) {
1037                         $this->unload( $lang );
1038                 }
1039         }
1040
1041         /**
1042          * Disable the storage backend
1043          */
1044         public function disableBackend() {
1045                 $this->store = new LCStoreNull;
1046                 $this->manualRecache = false;
1047         }
1048 }
1049
1050 /**
1051  * Interface for the persistence layer of LocalisationCache.
1052  *
1053  * The persistence layer is two-level hierarchical cache. The first level
1054  * is the language, the second level is the item or subitem.
1055  *
1056  * Since the data for a whole language is rebuilt in one operation, it needs
1057  * to have a fast and atomic method for deleting or replacing all of the
1058  * current data for a given language. The interface reflects this bulk update
1059  * operation. Callers writing to the cache must first call startWrite(), then
1060  * will call set() a couple of thousand times, then will call finishWrite()
1061  * to commit the operation. When finishWrite() is called, the cache is
1062  * expected to delete all data previously stored for that language.
1063  *
1064  * The values stored are PHP variables suitable for serialize(). Implementations
1065  * of LCStore are responsible for serializing and unserializing.
1066  */
1067 interface LCStore {
1068         /**
1069          * Get a value.
1070          * @param string $code Language code
1071          * @param string $key Cache key
1072          */
1073         function get( $code, $key );
1074
1075         /**
1076          * Start a write transaction.
1077          * @param string $code Language code
1078          */
1079         function startWrite( $code );
1080
1081         /**
1082          * Finish a write transaction.
1083          */
1084         function finishWrite();
1085
1086         /**
1087          * Set a key to a given value. startWrite() must be called before this
1088          * is called, and finishWrite() must be called afterwards.
1089          * @param string $key
1090          * @param mixed $value
1091          */
1092         function set( $key, $value );
1093 }
1094
1095 /**
1096  * LCStore implementation which uses PHP accelerator to store data.
1097  * This will work if one of XCache, WinCache or APC cacher is configured.
1098  * (See ObjectCache.php)
1099  */
1100 class LCStoreAccel implements LCStore {
1101         private $currentLang;
1102         private $keys;
1103
1104         public function __construct() {
1105                 $this->cache = wfGetCache( CACHE_ACCEL );
1106         }
1107
1108         public function get( $code, $key ) {
1109                 $k = wfMemcKey( 'l10n', $code, 'k', $key );
1110                 $r = $this->cache->get( $k );
1111
1112                 return $r === false ? null : $r;
1113         }
1114
1115         public function startWrite( $code ) {
1116                 $k = wfMemcKey( 'l10n', $code, 'l' );
1117                 $keys = $this->cache->get( $k );
1118                 if ( $keys ) {
1119                         foreach ( $keys as $k ) {
1120                                 $this->cache->delete( $k );
1121                         }
1122                 }
1123                 $this->currentLang = $code;
1124                 $this->keys = array();
1125         }
1126
1127         public function finishWrite() {
1128                 if ( $this->currentLang ) {
1129                         $k = wfMemcKey( 'l10n', $this->currentLang, 'l' );
1130                         $this->cache->set( $k, array_keys( $this->keys ) );
1131                 }
1132                 $this->currentLang = null;
1133                 $this->keys = array();
1134         }
1135
1136         public function set( $key, $value ) {
1137                 if ( $this->currentLang ) {
1138                         $k = wfMemcKey( 'l10n', $this->currentLang, 'k', $key );
1139                         $this->keys[$k] = true;
1140                         $this->cache->set( $k, $value );
1141                 }
1142         }
1143 }
1144
1145 /**
1146  * LCStore implementation which uses the standard DB functions to store data.
1147  * This will work on any MediaWiki installation.
1148  */
1149 class LCStoreDB implements LCStore {
1150         private $currentLang;
1151         private $writesDone = false;
1152
1153         /**
1154          * @var DatabaseBase
1155          */
1156         private $dbw;
1157         private $batch;
1158         private $readOnly = false;
1159
1160         public function get( $code, $key ) {
1161                 if ( $this->writesDone ) {
1162                         $db = wfGetDB( DB_MASTER );
1163                 } else {
1164                         $db = wfGetDB( DB_SLAVE );
1165                 }
1166                 $row = $db->selectRow( 'l10n_cache', array( 'lc_value' ),
1167                         array( 'lc_lang' => $code, 'lc_key' => $key ), __METHOD__ );
1168                 if ( $row ) {
1169                         return unserialize( $row->lc_value );
1170                 } else {
1171                         return null;
1172                 }
1173         }
1174
1175         public function startWrite( $code ) {
1176                 if ( $this->readOnly ) {
1177                         return;
1178                 }
1179
1180                 if ( !$code ) {
1181                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
1182                 }
1183
1184                 $this->dbw = wfGetDB( DB_MASTER );
1185                 try {
1186                         $this->dbw->begin( __METHOD__ );
1187                         $this->dbw->delete( 'l10n_cache', array( 'lc_lang' => $code ), __METHOD__ );
1188                 } catch ( DBQueryError $e ) {
1189                         if ( $this->dbw->wasReadOnlyError() ) {
1190                                 $this->readOnly = true;
1191                                 $this->dbw->rollback( __METHOD__ );
1192
1193                                 return;
1194                         } else {
1195                                 throw $e;
1196                         }
1197                 }
1198
1199                 $this->currentLang = $code;
1200                 $this->batch = array();
1201         }
1202
1203         public function finishWrite() {
1204                 if ( $this->readOnly ) {
1205                         return;
1206                 }
1207
1208                 if ( $this->batch ) {
1209                         $this->dbw->insert( 'l10n_cache', $this->batch, __METHOD__ );
1210                 }
1211
1212                 $this->dbw->commit( __METHOD__ );
1213                 $this->currentLang = null;
1214                 $this->dbw = null;
1215                 $this->batch = array();
1216                 $this->writesDone = true;
1217         }
1218
1219         public function set( $key, $value ) {
1220                 if ( $this->readOnly ) {
1221                         return;
1222                 }
1223
1224                 if ( is_null( $this->currentLang ) ) {
1225                         throw new MWException( __CLASS__ . ': must call startWrite() before calling set()' );
1226                 }
1227
1228                 $this->batch[] = array(
1229                         'lc_lang' => $this->currentLang,
1230                         'lc_key' => $key,
1231                         'lc_value' => serialize( $value ) );
1232
1233                 if ( count( $this->batch ) >= 100 ) {
1234                         $this->dbw->insert( 'l10n_cache', $this->batch, __METHOD__ );
1235                         $this->batch = array();
1236                 }
1237         }
1238 }
1239
1240 /**
1241  * LCStore implementation which stores data as a collection of CDB files in the
1242  * directory given by $wgCacheDirectory. If $wgCacheDirectory is not set, this
1243  * will throw an exception.
1244  *
1245  * Profiling indicates that on Linux, this implementation outperforms MySQL if
1246  * the directory is on a local filesystem and there is ample kernel cache
1247  * space. The performance advantage is greater when the DBA extension is
1248  * available than it is with the PHP port.
1249  *
1250  * See Cdb.php and http://cr.yp.to/cdb.html
1251  */
1252 class LCStoreCDB implements LCStore {
1253         /** @var CdbReader[] */
1254         private $readers;
1255
1256         /** @var CdbWriter */
1257         private $writer;
1258
1259         /** @var string Current language code */
1260         private $currentLang;
1261
1262         /** @var bool|string Cache directory. False if not set */
1263         private $directory;
1264
1265         function __construct( $conf = array() ) {
1266                 global $wgCacheDirectory;
1267
1268                 if ( isset( $conf['directory'] ) ) {
1269                         $this->directory = $conf['directory'];
1270                 } else {
1271                         $this->directory = $wgCacheDirectory;
1272                 }
1273         }
1274
1275         public function get( $code, $key ) {
1276                 if ( !isset( $this->readers[$code] ) ) {
1277                         $fileName = $this->getFileName( $code );
1278
1279                         $this->readers[$code] = false;
1280                         if ( file_exists( $fileName ) ) {
1281                                 try {
1282                                         $this->readers[$code] = CdbReader::open( $fileName );
1283                                 } catch ( CdbException $e ) {
1284                                         wfDebug( __METHOD__ . ": unable to open cdb file for reading" );
1285                                 }
1286                         }
1287                 }
1288
1289                 if ( !$this->readers[$code] ) {
1290                         return null;
1291                 } else {
1292                         $value = false;
1293                         try {
1294                                 $value = $this->readers[$code]->get( $key );
1295                         } catch ( CdbException $e ) {
1296                                 wfDebug( __METHOD__ . ": CdbException caught, error message was "
1297                                         . $e->getMessage() );
1298                         }
1299                         if ( $value === false ) {
1300                                 return null;
1301                         }
1302
1303                         return unserialize( $value );
1304                 }
1305         }
1306
1307         public function startWrite( $code ) {
1308                 if ( !file_exists( $this->directory ) ) {
1309                         if ( !wfMkdirParents( $this->directory, null, __METHOD__ ) ) {
1310                                 throw new MWException( "Unable to create the localisation store " .
1311                                         "directory \"{$this->directory}\"" );
1312                         }
1313                 }
1314
1315                 // Close reader to stop permission errors on write
1316                 if ( !empty( $this->readers[$code] ) ) {
1317                         $this->readers[$code]->close();
1318                 }
1319
1320                 try {
1321                         $this->writer = CdbWriter::open( $this->getFileName( $code ) );
1322                 } catch ( CdbException $e ) {
1323                         throw new MWException( $e->getMessage() );
1324                 }
1325                 $this->currentLang = $code;
1326         }
1327
1328         public function finishWrite() {
1329                 // Close the writer
1330                 try {
1331                         $this->writer->close();
1332                 } catch ( CdbException $e ) {
1333                         throw new MWException( $e->getMessage() );
1334                 }
1335                 $this->writer = null;
1336                 unset( $this->readers[$this->currentLang] );
1337                 $this->currentLang = null;
1338         }
1339
1340         public function set( $key, $value ) {
1341                 if ( is_null( $this->writer ) ) {
1342                         throw new MWException( __CLASS__ . ': must call startWrite() before calling set()' );
1343                 }
1344                 try {
1345                         $this->writer->set( $key, serialize( $value ) );
1346                 } catch ( CdbException $e ) {
1347                         throw new MWException( $e->getMessage() );
1348                 }
1349         }
1350
1351         protected function getFileName( $code ) {
1352                 if ( strval( $code ) === '' || strpos( $code, '/' ) !== false ) {
1353                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
1354                 }
1355
1356                 return "{$this->directory}/l10n_cache-$code.cdb";
1357         }
1358 }
1359
1360 /**
1361  * Null store backend, used to avoid DB errors during install
1362  */
1363 class LCStoreNull implements LCStore {
1364         public function get( $code, $key ) {
1365                 return null;
1366         }
1367
1368         public function startWrite( $code ) {
1369         }
1370
1371         public function finishWrite() {
1372         }
1373
1374         public function set( $key, $value ) {
1375         }
1376 }
1377
1378 /**
1379  * A localisation cache optimised for loading large amounts of data for many
1380  * languages. Used by rebuildLocalisationCache.php.
1381  */
1382 class LocalisationCacheBulkLoad extends LocalisationCache {
1383         /**
1384          * A cache of the contents of data files.
1385          * Core files are serialized to avoid using ~1GB of RAM during a recache.
1386          */
1387         private $fileCache = array();
1388
1389         /**
1390          * Most recently used languages. Uses the linked-list aspect of PHP hashtables
1391          * to keep the most recently used language codes at the end of the array, and
1392          * the language codes that are ready to be deleted at the beginning.
1393          */
1394         private $mruLangs = array();
1395
1396         /**
1397          * Maximum number of languages that may be loaded into $this->data
1398          */
1399         private $maxLoadedLangs = 10;
1400
1401         /**
1402          * @param $fileName
1403          * @param $fileType
1404          * @return array|mixed
1405          */
1406         protected function readPHPFile( $fileName, $fileType ) {
1407                 $serialize = $fileType === 'core';
1408                 if ( !isset( $this->fileCache[$fileName][$fileType] ) ) {
1409                         $data = parent::readPHPFile( $fileName, $fileType );
1410
1411                         if ( $serialize ) {
1412                                 $encData = serialize( $data );
1413                         } else {
1414                                 $encData = $data;
1415                         }
1416
1417                         $this->fileCache[$fileName][$fileType] = $encData;
1418
1419                         return $data;
1420                 } elseif ( $serialize ) {
1421                         return unserialize( $this->fileCache[$fileName][$fileType] );
1422                 } else {
1423                         return $this->fileCache[$fileName][$fileType];
1424                 }
1425         }
1426
1427         /**
1428          * @param $code
1429          * @param $key
1430          * @return mixed
1431          */
1432         public function getItem( $code, $key ) {
1433                 unset( $this->mruLangs[$code] );
1434                 $this->mruLangs[$code] = true;
1435
1436                 return parent::getItem( $code, $key );
1437         }
1438
1439         /**
1440          * @param $code
1441          * @param $key
1442          * @param $subkey
1443          * @return
1444          */
1445         public function getSubitem( $code, $key, $subkey ) {
1446                 unset( $this->mruLangs[$code] );
1447                 $this->mruLangs[$code] = true;
1448
1449                 return parent::getSubitem( $code, $key, $subkey );
1450         }
1451
1452         /**
1453          * @param $code
1454          */
1455         public function recache( $code ) {
1456                 parent::recache( $code );
1457                 unset( $this->mruLangs[$code] );
1458                 $this->mruLangs[$code] = true;
1459                 $this->trimCache();
1460         }
1461
1462         /**
1463          * @param $code
1464          */
1465         public function unload( $code ) {
1466                 unset( $this->mruLangs[$code] );
1467                 parent::unload( $code );
1468         }
1469
1470         /**
1471          * Unload cached languages until there are less than $this->maxLoadedLangs
1472          */
1473         protected function trimCache() {
1474                 while ( count( $this->data ) > $this->maxLoadedLangs && count( $this->mruLangs ) ) {
1475                         reset( $this->mruLangs );
1476                         $code = key( $this->mruLangs );
1477                         wfDebug( __METHOD__ . ": unloading $code\n" );
1478                         $this->unload( $code );
1479                 }
1480         }
1481 }