includes/cache/LocalisationCache.php

   1 <?php
   2 /**
   3  * Cache of the contents of localisation files.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 use Cdb\Exception as CdbException;
  24 use Cdb\Reader as CdbReader;
  25 use Cdb\Writer as CdbWriter;
  26
  27 /**
  28  * Class for caching the contents of localisation files, Messages*.php
  29  * and *.i18n.php.
  30  *
  31  * An instance of this class is available using Language::getLocalisationCache().
  32  *
  33  * The values retrieved from here are merged, containing items from extension
  34  * files, core messages files and the language fallback sequence (e.g. zh-cn ->
  35  * zh-hans -> en ). Some common errors are corrected, for example namespace
  36  * names with spaces instead of underscores, but heavyweight processing, such
  37  * as grammatical transformation, is done by the caller.
  38  */
  39 class LocalisationCache {
  40         const VERSION = 3;
  41
  42         /** Configuration associative array */
  43         private $conf;
  44
  45         /**
  46          * True if recaching should only be done on an explicit call to recache().
  47          * Setting this reduces the overhead of cache freshness checking, which
  48          * requires doing a stat() for every extension i18n file.
  49          */
  50         private $manualRecache = false;
  51
  52         /**
  53          * True to treat all files as expired until they are regenerated by this object.
  54          */
  55         private $forceRecache = false;
  56
  57         /**
  58          * The cache data. 3-d array, where the first key is the language code,
  59          * the second key is the item key e.g. 'messages', and the third key is
  60          * an item specific subkey index. Some items are not arrays and so for those
  61          * items, there are no subkeys.
  62          */
  63         protected $data = array();
  64
  65         /**
  66          * The persistent store object. An instance of LCStore.
  67          *
  68          * @var LCStore
  69          */
  70         private $store;
  71
  72         /**
  73          * A 2-d associative array, code/key, where presence indicates that the item
  74          * is loaded. Value arbitrary.
  75          *
  76          * For split items, if set, this indicates that all of the subitems have been
  77          * loaded.
  78          */
  79         private $loadedItems = array();
  80
  81         /**
  82          * A 3-d associative array, code/key/subkey, where presence indicates that
  83          * the subitem is loaded. Only used for the split items, i.e. messages.
  84          */
  85         private $loadedSubitems = array();
  86
  87         /**
  88          * An array where presence of a key indicates that that language has been
  89          * initialised. Initialisation includes checking for cache expiry and doing
  90          * any necessary updates.
  91          */
  92         private $initialisedLangs = array();
  93
  94         /**
  95          * An array mapping non-existent pseudo-languages to fallback languages. This
  96          * is filled by initShallowFallback() when data is requested from a language
  97          * that lacks a Messages*.php file.
  98          */
  99         private $shallowFallbacks = array();
 100
 101         /**
 102          * An array where the keys are codes that have been recached by this instance.
 103          */
 104         private $recachedLangs = array();
 105
 106         /**
 107          * All item keys
 108          */
 109         static public $allKeys = array(
 110                 'fallback', 'namespaceNames', 'bookstoreList',
 111                 'magicWords', 'messages', 'rtl', 'capitalizeAllNouns', 'digitTransformTable',
 112                 'separatorTransformTable', 'fallback8bitEncoding', 'linkPrefixExtension',
 113                 'linkTrail', 'linkPrefixCharset', 'namespaceAliases',
 114                 'dateFormats', 'datePreferences', 'datePreferenceMigrationMap',
 115                 'defaultDateFormat', 'extraUserToggles', 'specialPageAliases',
 116                 'imageFiles', 'preloadedMessages', 'namespaceGenderAliases',
 117                 'digitGroupingPattern', 'pluralRules', 'pluralRuleTypes', 'compiledPluralRules',
 118         );
 119
 120         /**
 121          * Keys for items which consist of associative arrays, which may be merged
 122          * by a fallback sequence.
 123          */
 124         static public $mergeableMapKeys = array( 'messages', 'namespaceNames',
 125                 'dateFormats', 'imageFiles', 'preloadedMessages'
 126         );
 127
 128         /**
 129          * Keys for items which are a numbered array.
 130          */
 131         static public $mergeableListKeys = array( 'extraUserToggles' );
 132
 133         /**
 134          * Keys for items which contain an array of arrays of equivalent aliases
 135          * for each subitem. The aliases may be merged by a fallback sequence.
 136          */
 137         static public $mergeableAliasListKeys = array( 'specialPageAliases' );
 138
 139         /**
 140          * Keys for items which contain an associative array, and may be merged if
 141          * the primary value contains the special array key "inherit". That array
 142          * key is removed after the first merge.
 143          */
 144         static public $optionalMergeKeys = array( 'bookstoreList' );
 145
 146         /**
 147          * Keys for items that are formatted like $magicWords
 148          */
 149         static public $magicWordKeys = array( 'magicWords' );
 150
 151         /**
 152          * Keys for items where the subitems are stored in the backend separately.
 153          */
 154         static public $splitKeys = array( 'messages' );
 155
 156         /**
 157          * Keys which are loaded automatically by initLanguage()
 158          */
 159         static public $preloadedKeys = array( 'dateFormats', 'namespaceNames' );
 160
 161         /**
 162          * Associative array of cached plural rules. The key is the language code,
 163          * the value is an array of plural rules for that language.
 164          */
 165         private $pluralRules = null;
 166
 167         /**
 168          * Associative array of cached plural rule types. The key is the language
 169          * code, the value is an array of plural rule types for that language. For
 170          * example, $pluralRuleTypes['ar'] = ['zero', 'one', 'two', 'few', 'many'].
 171          * The index for each rule type matches the index for the rule in
 172          * $pluralRules, thus allowing correlation between the two. The reason we
 173          * don't just use the type names as the keys in $pluralRules is because
 174          * Language::convertPlural applies the rules based on numeric order (or
 175          * explicit numeric parameter), not based on the name of the rule type. For
 176          * example, {{plural:count|wordform1|wordform2|wordform3}}, rather than
 177          * {{plural:count|one=wordform1|two=wordform2|many=wordform3}}.
 178          */
 179         private $pluralRuleTypes = null;
 180
 181         private $mergeableKeys = null;
 182
 183         /**
 184          * Constructor.
 185          * For constructor parameters, see the documentation in DefaultSettings.php
 186          * for $wgLocalisationCacheConf.
 187          *
 188          * @param array $conf
 189          * @throws MWException
 190          */
 191         function __construct( $conf ) {
 192                 global $wgCacheDirectory;
 193
 194                 $this->conf = $conf;
 195                 $storeConf = array();
 196                 if ( !empty( $conf['storeClass'] ) ) {
 197                         $storeClass = $conf['storeClass'];
 198                 } else {
 199                         switch ( $conf['store'] ) {
 200                                 case 'files':
 201                                 case 'file':
 202                                         $storeClass = 'LCStoreCDB';
 203                                         break;
 204                                 case 'db':
 205                                         $storeClass = 'LCStoreDB';
 206                                         break;
 207                                 case 'detect':
 208                                         $storeClass = $wgCacheDirectory ? 'LCStoreCDB' : 'LCStoreDB';
 209                                         break;
 210                                 default:
 211                                         throw new MWException(
 212                                                 'Please set $wgLocalisationCacheConf[\'store\'] to something sensible.' );
 213                         }
 214                 }
 215
 216                 wfDebugLog( 'caches', get_class( $this ) . ": using store $storeClass" );
 217                 if ( !empty( $conf['storeDirectory'] ) ) {
 218                         $storeConf['directory'] = $conf['storeDirectory'];
 219                 }
 220
 221                 $this->store = new $storeClass( $storeConf );
 222                 foreach ( array( 'manualRecache', 'forceRecache' ) as $var ) {
 223                         if ( isset( $conf[$var] ) ) {
 224                                 $this->$var = $conf[$var];
 225                         }
 226                 }
 227         }
 228
 229         /**
 230          * Returns true if the given key is mergeable, that is, if it is an associative
 231          * array which can be merged through a fallback sequence.
 232          * @param string $key
 233          * @return bool
 234          */
 235         public function isMergeableKey( $key ) {
 236                 if ( $this->mergeableKeys === null ) {
 237                         $this->mergeableKeys = array_flip( array_merge(
 238                                 self::$mergeableMapKeys,
 239                                 self::$mergeableListKeys,
 240                                 self::$mergeableAliasListKeys,
 241                                 self::$optionalMergeKeys,
 242                                 self::$magicWordKeys
 243                         ) );
 244                 }
 245
 246                 return isset( $this->mergeableKeys[$key] );
 247         }
 248
 249         /**
 250          * Get a cache item.
 251          *
 252          * Warning: this may be slow for split items (messages), since it will
 253          * need to fetch all of the subitems from the cache individually.
 254          * @param string $code
 255          * @param string $key
 256          * @return mixed
 257          */
 258         public function getItem( $code, $key ) {
 259                 if ( !isset( $this->loadedItems[$code][$key] ) ) {
 260                         wfProfileIn( __METHOD__ . '-load' );
 261                         $this->loadItem( $code, $key );
 262                         wfProfileOut( __METHOD__ . '-load' );
 263                 }
 264
 265                 if ( $key === 'fallback' && isset( $this->shallowFallbacks[$code] ) ) {
 266                         return $this->shallowFallbacks[$code];
 267                 }
 268
 269                 return $this->data[$code][$key];
 270         }
 271
 272         /**
 273          * Get a subitem, for instance a single message for a given language.
 274          * @param string $code
 275          * @param string $key
 276          * @param string $subkey
 277          * @return mixed|null
 278          */
 279         public function getSubitem( $code, $key, $subkey ) {
 280                 if ( !isset( $this->loadedSubitems[$code][$key][$subkey] ) &&
 281                         !isset( $this->loadedItems[$code][$key] )
 282                 ) {
 283                         wfProfileIn( __METHOD__ . '-load' );
 284                         $this->loadSubitem( $code, $key, $subkey );
 285                         wfProfileOut( __METHOD__ . '-load' );
 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                 wfProfileIn( __METHOD__ );
 513                 // Disable APC caching
 514                 wfSuppressWarnings();
 515                 $_apcEnabled = ini_set( 'apc.cache_by_default', '0' );
 516                 wfRestoreWarnings();
 517
 518                 include $_fileName;
 519
 520                 wfSuppressWarnings();
 521                 ini_set( 'apc.cache_by_default', $_apcEnabled );
 522                 wfRestoreWarnings();
 523
 524                 if ( $_fileType == 'core' || $_fileType == 'extension' ) {
 525                         $data = compact( self::$allKeys );
 526                 } elseif ( $_fileType == 'aliases' ) {
 527                         $data = compact( 'aliases' );
 528                 } else {
 529                         wfProfileOut( __METHOD__ );
 530                         throw new MWException( __METHOD__ . ": Invalid file type: $_fileType" );
 531                 }
 532                 wfProfileOut( __METHOD__ );
 533
 534                 return $data;
 535         }
 536
 537         /**
 538          * Read a JSON file containing localisation messages.
 539          * @param string $fileName Name of file to read
 540          * @throws MWException If there is a syntax error in the JSON file
 541          * @return array Array with a 'messages' key, or empty array if the file doesn't exist
 542          */
 543         public function readJSONFile( $fileName ) {
 544                 wfProfileIn( __METHOD__ );
 545
 546                 if ( !is_readable( $fileName ) ) {
 547                         wfProfileOut( __METHOD__ );
 548
 549                         return array();
 550                 }
 551
 552                 $json = file_get_contents( $fileName );
 553                 if ( $json === false ) {
 554                         wfProfileOut( __METHOD__ );
 555
 556                         return array();
 557                 }
 558
 559                 $data = FormatJson::decode( $json, true );
 560                 if ( $data === null ) {
 561                         wfProfileOut( __METHOD__ );
 562
 563                         throw new MWException( __METHOD__ . ": Invalid JSON file: $fileName" );
 564                 }
 565
 566                 // Remove keys starting with '@', they're reserved for metadata and non-message data
 567                 foreach ( $data as $key => $unused ) {
 568                         if ( $key === '' || $key[0] === '@' ) {
 569                                 unset( $data[$key] );
 570                         }
 571                 }
 572
 573                 wfProfileOut( __METHOD__ );
 574
 575                 // The JSON format only supports messages, none of the other variables, so wrap the data
 576                 return array( 'messages' => $data );
 577         }
 578
 579         /**
 580          * Get the compiled plural rules for a given language from the XML files.
 581          * @since 1.20
 582          * @param string $code
 583          * @return array|null
 584          */
 585         public function getCompiledPluralRules( $code ) {
 586                 $rules = $this->getPluralRules( $code );
 587                 if ( $rules === null ) {
 588                         return null;
 589                 }
 590                 try {
 591                         $compiledRules = CLDRPluralRuleEvaluator::compile( $rules );
 592                 } catch ( CLDRPluralRuleError $e ) {
 593                         wfDebugLog( 'l10n', $e->getMessage() );
 594
 595                         return array();
 596                 }
 597
 598                 return $compiledRules;
 599         }
 600
 601         /**
 602          * Get the plural rules for a given language from the XML files.
 603          * Cached.
 604          * @since 1.20
 605          * @param string $code
 606          * @return array|null
 607          */
 608         public function getPluralRules( $code ) {
 609                 if ( $this->pluralRules === null ) {
 610                         $this->loadPluralFiles();
 611                 }
 612                 if ( !isset( $this->pluralRules[$code] ) ) {
 613                         return null;
 614                 } else {
 615                         return $this->pluralRules[$code];
 616                 }
 617         }
 618
 619         /**
 620          * Get the plural rule types for a given language from the XML files.
 621          * Cached.
 622          * @since 1.22
 623          * @param string $code
 624          * @return array|null
 625          */
 626         public function getPluralRuleTypes( $code ) {
 627                 if ( $this->pluralRuleTypes === null ) {
 628                         $this->loadPluralFiles();
 629                 }
 630                 if ( !isset( $this->pluralRuleTypes[$code] ) ) {
 631                         return null;
 632                 } else {
 633                         return $this->pluralRuleTypes[$code];
 634                 }
 635         }
 636
 637         /**
 638          * Load the plural XML files.
 639          */
 640         protected function loadPluralFiles() {
 641                 global $IP;
 642                 $cldrPlural = "$IP/languages/data/plurals.xml";
 643                 $mwPlural = "$IP/languages/data/plurals-mediawiki.xml";
 644                 // Load CLDR plural rules
 645                 $this->loadPluralFile( $cldrPlural );
 646                 if ( file_exists( $mwPlural ) ) {
 647                         // Override or extend
 648                         $this->loadPluralFile( $mwPlural );
 649                 }
 650         }
 651
 652         /**
 653          * Load a plural XML file with the given filename, compile the relevant
 654          * rules, and save the compiled rules in a process-local cache.
 655          *
 656          * @param string $fileName
 657          */
 658         protected function loadPluralFile( $fileName ) {
 659                 $doc = new DOMDocument;
 660                 $doc->load( $fileName );
 661                 $rulesets = $doc->getElementsByTagName( "pluralRules" );
 662                 foreach ( $rulesets as $ruleset ) {
 663                         $codes = $ruleset->getAttribute( 'locales' );
 664                         $rules = array();
 665                         $ruleTypes = array();
 666                         $ruleElements = $ruleset->getElementsByTagName( "pluralRule" );
 667                         foreach ( $ruleElements as $elt ) {
 668                                 $ruleType = $elt->getAttribute( 'count' );
 669                                 if ( $ruleType === 'other' ) {
 670                                         // Don't record "other" rules, which have an empty condition
 671                                         continue;
 672                                 }
 673                                 $rules[] = $elt->nodeValue;
 674                                 $ruleTypes[] = $ruleType;
 675                         }
 676                         foreach ( explode( ' ', $codes ) as $code ) {
 677                                 $this->pluralRules[$code] = $rules;
 678                                 $this->pluralRuleTypes[$code] = $ruleTypes;
 679                         }
 680                 }
 681         }
 682
 683         /**
 684          * Read the data from the source files for a given language, and register
 685          * the relevant dependencies in the $deps array. If the localisation
 686          * exists, the data array is returned, otherwise false is returned.
 687          *
 688          * @param string $code
 689          * @param array $deps
 690          * @return array
 691          */
 692         protected function readSourceFilesAndRegisterDeps( $code, &$deps ) {
 693                 global $IP;
 694                 wfProfileIn( __METHOD__ );
 695
 696                 // This reads in the PHP i18n file with non-messages l10n data
 697                 $fileName = Language::getMessagesFileName( $code );
 698                 if ( !file_exists( $fileName ) ) {
 699                         $data = array();
 700                 } else {
 701                         $deps[] = new FileDependency( $fileName );
 702                         $data = $this->readPHPFile( $fileName, 'core' );
 703                 }
 704
 705                 # Load CLDR plural rules for JavaScript
 706                 $data['pluralRules'] = $this->getPluralRules( $code );
 707                 # And for PHP
 708                 $data['compiledPluralRules'] = $this->getCompiledPluralRules( $code );
 709                 # Load plural rule types
 710                 $data['pluralRuleTypes'] = $this->getPluralRuleTypes( $code );
 711
 712                 $deps['plurals'] = new FileDependency( "$IP/languages/data/plurals.xml" );
 713                 $deps['plurals-mw'] = new FileDependency( "$IP/languages/data/plurals-mediawiki.xml" );
 714
 715                 wfProfileOut( __METHOD__ );
 716
 717                 return $data;
 718         }
 719
 720         /**
 721          * Merge two localisation values, a primary and a fallback, overwriting the
 722          * primary value in place.
 723          * @param string $key
 724          * @param mixed $value
 725          * @param mixed $fallbackValue
 726          */
 727         protected function mergeItem( $key, &$value, $fallbackValue ) {
 728                 if ( !is_null( $value ) ) {
 729                         if ( !is_null( $fallbackValue ) ) {
 730                                 if ( in_array( $key, self::$mergeableMapKeys ) ) {
 731                                         $value = $value + $fallbackValue;
 732                                 } elseif ( in_array( $key, self::$mergeableListKeys ) ) {
 733                                         $value = array_unique( array_merge( $fallbackValue, $value ) );
 734                                 } elseif ( in_array( $key, self::$mergeableAliasListKeys ) ) {
 735                                         $value = array_merge_recursive( $value, $fallbackValue );
 736                                 } elseif ( in_array( $key, self::$optionalMergeKeys ) ) {
 737                                         if ( !empty( $value['inherit'] ) ) {
 738                                                 $value = array_merge( $fallbackValue, $value );
 739                                         }
 740
 741                                         if ( isset( $value['inherit'] ) ) {
 742                                                 unset( $value['inherit'] );
 743                                         }
 744                                 } elseif ( in_array( $key, self::$magicWordKeys ) ) {
 745                                         $this->mergeMagicWords( $value, $fallbackValue );
 746                                 }
 747                         }
 748                 } else {
 749                         $value = $fallbackValue;
 750                 }
 751         }
 752
 753         /**
 754          * @param mixed $value
 755          * @param mixed $fallbackValue
 756          */
 757         protected function mergeMagicWords( &$value, $fallbackValue ) {
 758                 foreach ( $fallbackValue as $magicName => $fallbackInfo ) {
 759                         if ( !isset( $value[$magicName] ) ) {
 760                                 $value[$magicName] = $fallbackInfo;
 761                         } else {
 762                                 $oldSynonyms = array_slice( $fallbackInfo, 1 );
 763                                 $newSynonyms = array_slice( $value[$magicName], 1 );
 764                                 $synonyms = array_values( array_unique( array_merge(
 765                                         $newSynonyms, $oldSynonyms ) ) );
 766                                 $value[$magicName] = array_merge( array( $fallbackInfo[0] ), $synonyms );
 767                         }
 768                 }
 769         }
 770
 771         /**
 772          * Given an array mapping language code to localisation value, such as is
 773          * found in extension *.i18n.php files, iterate through a fallback sequence
 774          * to merge the given data with an existing primary value.
 775          *
 776          * Returns true if any data from the extension array was used, false
 777          * otherwise.
 778          * @param array $codeSequence
 779          * @param string $key
 780          * @param mixed $value
 781          * @param mixed $fallbackValue
 782          * @return bool
 783          */
 784         protected function mergeExtensionItem( $codeSequence, $key, &$value, $fallbackValue ) {
 785                 $used = false;
 786                 foreach ( $codeSequence as $code ) {
 787                         if ( isset( $fallbackValue[$code] ) ) {
 788                                 $this->mergeItem( $key, $value, $fallbackValue[$code] );
 789                                 $used = true;
 790                         }
 791                 }
 792
 793                 return $used;
 794         }
 795
 796         /**
 797          * Gets the combined list of messages dirs from
 798          * core and extensions
 799          *
 800          * @since 1.25
 801          * @return array
 802          */
 803         public function getMessagesDirs() {
 804                 global $wgMessagesDirs, $IP;
 805                 return array(
 806                         'core' => "$IP/languages/i18n",
 807                         'api' => "$IP/includes/api/i18n",
 808                         'oojs-ui' => "$IP/resources/lib/oojs-ui/i18n",
 809                 ) + $wgMessagesDirs;
 810         }
 811
 812         /**
 813          * Load localisation data for a given language for both core and extensions
 814          * and save it to the persistent cache store and the process cache
 815          * @param string $code
 816          * @throws MWException
 817          */
 818         public function recache( $code ) {
 819                 global $wgExtensionMessagesFiles;
 820                 wfProfileIn( __METHOD__ );
 821
 822                 if ( !$code ) {
 823                         wfProfileOut( __METHOD__ );
 824                         throw new MWException( "Invalid language code requested" );
 825                 }
 826                 $this->recachedLangs[$code] = true;
 827
 828                 # Initial values
 829                 $initialData = array_combine(
 830                         self::$allKeys,
 831                         array_fill( 0, count( self::$allKeys ), null ) );
 832                 $coreData = $initialData;
 833                 $deps = array();
 834
 835                 # Load the primary localisation from the source file
 836                 $data = $this->readSourceFilesAndRegisterDeps( $code, $deps );
 837                 if ( $data === false ) {
 838                         wfDebug( __METHOD__ . ": no localisation file for $code, using fallback to en\n" );
 839                         $coreData['fallback'] = 'en';
 840                 } else {
 841                         wfDebug( __METHOD__ . ": got localisation for $code from source\n" );
 842
 843                         # Merge primary localisation
 844                         foreach ( $data as $key => $value ) {
 845                                 $this->mergeItem( $key, $coreData[$key], $value );
 846                         }
 847                 }
 848
 849                 # Fill in the fallback if it's not there already
 850                 if ( is_null( $coreData['fallback'] ) ) {
 851                         $coreData['fallback'] = $code === 'en' ? false : 'en';
 852                 }
 853                 if ( $coreData['fallback'] === false ) {
 854                         $coreData['fallbackSequence'] = array();
 855                 } else {
 856                         $coreData['fallbackSequence'] = array_map( 'trim', explode( ',', $coreData['fallback'] ) );
 857                         $len = count( $coreData['fallbackSequence'] );
 858
 859                         # Ensure that the sequence ends at en
 860                         if ( $coreData['fallbackSequence'][$len - 1] !== 'en' ) {
 861                                 $coreData['fallbackSequence'][] = 'en';
 862                         }
 863                 }
 864
 865                 $codeSequence = array_merge( array( $code ), $coreData['fallbackSequence'] );
 866                 $messageDirs = $this->getMessagesDirs();
 867
 868                 wfProfileIn( __METHOD__ . '-fallbacks' );
 869
 870                 # Load non-JSON localisation data for extensions
 871                 $extensionData = array_combine(
 872                         $codeSequence,
 873                         array_fill( 0, count( $codeSequence ), $initialData ) );
 874                 foreach ( $wgExtensionMessagesFiles as $extension => $fileName ) {
 875                         if ( isset( $messageDirs[$extension] ) ) {
 876                                 # This extension has JSON message data; skip the PHP shim
 877                                 continue;
 878                         }
 879
 880                         $data = $this->readPHPFile( $fileName, 'extension' );
 881                         $used = false;
 882
 883                         foreach ( $data as $key => $item ) {
 884                                 foreach ( $codeSequence as $csCode ) {
 885                                         if ( isset( $item[$csCode] ) ) {
 886                                                 $this->mergeItem( $key, $extensionData[$csCode][$key], $item[$csCode] );
 887                                                 $used = true;
 888                                         }
 889                                 }
 890                         }
 891
 892                         if ( $used ) {
 893                                 $deps[] = new FileDependency( $fileName );
 894                         }
 895                 }
 896
 897                 # Load the localisation data for each fallback, then merge it into the full array
 898                 $allData = $initialData;
 899                 foreach ( $codeSequence as $csCode ) {
 900                         $csData = $initialData;
 901
 902                         # Load core messages and the extension localisations.
 903                         foreach ( $messageDirs as $dirs ) {
 904                                 foreach ( (array)$dirs as $dir ) {
 905                                         $fileName = "$dir/$csCode.json";
 906                                         $data = $this->readJSONFile( $fileName );
 907
 908                                         foreach ( $data as $key => $item ) {
 909                                                 $this->mergeItem( $key, $csData[$key], $item );
 910                                         }
 911
 912                                         $deps[] = new FileDependency( $fileName );
 913                                 }
 914                         }
 915
 916                         # Merge non-JSON extension data
 917                         if ( isset( $extensionData[$csCode] ) ) {
 918                                 foreach ( $extensionData[$csCode] as $key => $item ) {
 919                                         $this->mergeItem( $key, $csData[$key], $item );
 920                                 }
 921                         }
 922
 923                         if ( $csCode === $code ) {
 924                                 # Merge core data into extension data
 925                                 foreach ( $coreData as $key => $item ) {
 926                                         $this->mergeItem( $key, $csData[$key], $item );
 927                                 }
 928                         } else {
 929                                 # Load the secondary localisation from the source file to
 930                                 # avoid infinite cycles on cyclic fallbacks
 931                                 $fbData = $this->readSourceFilesAndRegisterDeps( $csCode, $deps );
 932                                 if ( $fbData !== false ) {
 933                                         # Only merge the keys that make sense to merge
 934                                         foreach ( self::$allKeys as $key ) {
 935                                                 if ( !isset( $fbData[$key] ) ) {
 936                                                         continue;
 937                                                 }
 938
 939                                                 if ( is_null( $coreData[$key] ) || $this->isMergeableKey( $key ) ) {
 940                                                         $this->mergeItem( $key, $csData[$key], $fbData[$key] );
 941                                                 }
 942                                         }
 943                                 }
 944                         }
 945
 946                         # Allow extensions an opportunity to adjust the data for this
 947                         # fallback
 948                         wfRunHooks( 'LocalisationCacheRecacheFallback', array( $this, $csCode, &$csData ) );
 949
 950                         # Merge the data for this fallback into the final array
 951                         if ( $csCode === $code ) {
 952                                 $allData = $csData;
 953                         } else {
 954                                 foreach ( self::$allKeys as $key ) {
 955                                         if ( !isset( $csData[$key] ) ) {
 956                                                 continue;
 957                                         }
 958
 959                                         if ( is_null( $allData[$key] ) || $this->isMergeableKey( $key ) ) {
 960                                                 $this->mergeItem( $key, $allData[$key], $csData[$key] );
 961                                         }
 962                                 }
 963                         }
 964                 }
 965
 966                 wfProfileOut( __METHOD__ . '-fallbacks' );
 967
 968                 # Add cache dependencies for any referenced globals
 969                 $deps['wgExtensionMessagesFiles'] = new GlobalDependency( 'wgExtensionMessagesFiles' );
 970                 // $wgMessagesDirs is used in LocalisationCache::getMessagesDirs()
 971                 $deps['wgMessagesDirs'] = new GlobalDependency( 'wgMessagesDirs' );
 972                 $deps['version'] = new ConstantDependency( 'LocalisationCache::VERSION' );
 973
 974                 # Add dependencies to the cache entry
 975                 $allData['deps'] = $deps;
 976
 977                 # Replace spaces with underscores in namespace names
 978                 $allData['namespaceNames'] = str_replace( ' ', '_', $allData['namespaceNames'] );
 979
 980                 # And do the same for special page aliases. $page is an array.
 981                 foreach ( $allData['specialPageAliases'] as &$page ) {
 982                         $page = str_replace( ' ', '_', $page );
 983                 }
 984                 # Decouple the reference to prevent accidental damage
 985                 unset( $page );
 986
 987                 # If there were no plural rules, return an empty array
 988                 if ( $allData['pluralRules'] === null ) {
 989                         $allData['pluralRules'] = array();
 990                 }
 991                 if ( $allData['compiledPluralRules'] === null ) {
 992                         $allData['compiledPluralRules'] = array();
 993                 }
 994                 # If there were no plural rule types, return an empty array
 995                 if ( $allData['pluralRuleTypes'] === null ) {
 996                         $allData['pluralRuleTypes'] = array();
 997                 }
 998
 999                 # Set the list keys
1000                 $allData['list'] = array();
1001                 foreach ( self::$splitKeys as $key ) {
1002                         $allData['list'][$key] = array_keys( $allData[$key] );
1003                 }
1004                 # Run hooks
1005                 $purgeBlobs = true;
1006                 wfRunHooks( 'LocalisationCacheRecache', array( $this, $code, &$allData, &$purgeBlobs ) );
1007
1008                 if ( is_null( $allData['namespaceNames'] ) ) {
1009                         wfProfileOut( __METHOD__ );
1010                         throw new MWException( __METHOD__ . ': Localisation data failed sanity check! ' .
1011                                 'Check that your languages/messages/MessagesEn.php file is intact.' );
1012                 }
1013
1014                 # Set the preload key
1015                 $allData['preload'] = $this->buildPreload( $allData );
1016
1017                 # Save to the process cache and register the items loaded
1018                 $this->data[$code] = $allData;
1019                 foreach ( $allData as $key => $item ) {
1020                         $this->loadedItems[$code][$key] = true;
1021                 }
1022
1023                 # Save to the persistent cache
1024                 wfProfileIn( __METHOD__ . '-write' );
1025                 $this->store->startWrite( $code );
1026                 foreach ( $allData as $key => $value ) {
1027                         if ( in_array( $key, self::$splitKeys ) ) {
1028                                 foreach ( $value as $subkey => $subvalue ) {
1029                                         $this->store->set( "$key:$subkey", $subvalue );
1030                                 }
1031                         } else {
1032                                 $this->store->set( $key, $value );
1033                         }
1034                 }
1035                 $this->store->finishWrite();
1036                 wfProfileOut( __METHOD__ . '-write' );
1037
1038                 # Clear out the MessageBlobStore
1039                 # HACK: If using a null (i.e. disabled) storage backend, we
1040                 # can't write to the MessageBlobStore either
1041                 if ( $purgeBlobs && !$this->store instanceof LCStoreNull ) {
1042                         MessageBlobStore::getInstance()->clear();
1043                 }
1044
1045                 wfProfileOut( __METHOD__ );
1046         }
1047
1048         /**
1049          * Build the preload item from the given pre-cache data.
1050          *
1051          * The preload item will be loaded automatically, improving performance
1052          * for the commonly-requested items it contains.
1053          * @param array $data
1054          * @return array
1055          */
1056         protected function buildPreload( $data ) {
1057                 $preload = array( 'messages' => array() );
1058                 foreach ( self::$preloadedKeys as $key ) {
1059                         $preload[$key] = $data[$key];
1060                 }
1061
1062                 foreach ( $data['preloadedMessages'] as $subkey ) {
1063                         if ( isset( $data['messages'][$subkey] ) ) {
1064                                 $subitem = $data['messages'][$subkey];
1065                         } else {
1066                                 $subitem = null;
1067                         }
1068                         $preload['messages'][$subkey] = $subitem;
1069                 }
1070
1071                 return $preload;
1072         }
1073
1074         /**
1075          * Unload the data for a given language from the object cache.
1076          * Reduces memory usage.
1077          * @param string $code
1078          */
1079         public function unload( $code ) {
1080                 unset( $this->data[$code] );
1081                 unset( $this->loadedItems[$code] );
1082                 unset( $this->loadedSubitems[$code] );
1083                 unset( $this->initialisedLangs[$code] );
1084                 unset( $this->shallowFallbacks[$code] );
1085
1086                 foreach ( $this->shallowFallbacks as $shallowCode => $fbCode ) {
1087                         if ( $fbCode === $code ) {
1088                                 $this->unload( $shallowCode );
1089                         }
1090                 }
1091         }
1092
1093         /**
1094          * Unload all data
1095          */
1096         public function unloadAll() {
1097                 foreach ( $this->initialisedLangs as $lang => $unused ) {
1098                         $this->unload( $lang );
1099                 }
1100         }
1101
1102         /**
1103          * Disable the storage backend
1104          */
1105         public function disableBackend() {
1106                 $this->store = new LCStoreNull;
1107                 $this->manualRecache = false;
1108         }
1109 }
1110
1111 /**
1112  * Interface for the persistence layer of LocalisationCache.
1113  *
1114  * The persistence layer is two-level hierarchical cache. The first level
1115  * is the language, the second level is the item or subitem.
1116  *
1117  * Since the data for a whole language is rebuilt in one operation, it needs
1118  * to have a fast and atomic method for deleting or replacing all of the
1119  * current data for a given language. The interface reflects this bulk update
1120  * operation. Callers writing to the cache must first call startWrite(), then
1121  * will call set() a couple of thousand times, then will call finishWrite()
1122  * to commit the operation. When finishWrite() is called, the cache is
1123  * expected to delete all data previously stored for that language.
1124  *
1125  * The values stored are PHP variables suitable for serialize(). Implementations
1126  * of LCStore are responsible for serializing and unserializing.
1127  */
1128 interface LCStore {
1129         /**
1130          * Get a value.
1131          * @param string $code Language code
1132          * @param string $key Cache key
1133          */
1134         function get( $code, $key );
1135
1136         /**
1137          * Start a write transaction.
1138          * @param string $code Language code
1139          */
1140         function startWrite( $code );
1141
1142         /**
1143          * Finish a write transaction.
1144          */
1145         function finishWrite();
1146
1147         /**
1148          * Set a key to a given value. startWrite() must be called before this
1149          * is called, and finishWrite() must be called afterwards.
1150          * @param string $key
1151          * @param mixed $value
1152          */
1153         function set( $key, $value );
1154 }
1155
1156 /**
1157  * LCStore implementation which uses the standard DB functions to store data.
1158  * This will work on any MediaWiki installation.
1159  */
1160 class LCStoreDB implements LCStore {
1161         private $currentLang;
1162         private $writesDone = false;
1163
1164         /** @var DatabaseBase */
1165         private $dbw;
1166         /** @var array */
1167         private $batch = array();
1168
1169         private $readOnly = false;
1170
1171         public function get( $code, $key ) {
1172                 if ( $this->writesDone ) {
1173                         $db = wfGetDB( DB_MASTER );
1174                 } else {
1175                         $db = wfGetDB( DB_SLAVE );
1176                 }
1177                 $row = $db->selectRow( 'l10n_cache', array( 'lc_value' ),
1178                         array( 'lc_lang' => $code, 'lc_key' => $key ), __METHOD__ );
1179                 if ( $row ) {
1180                         return unserialize( $db->decodeBlob( $row->lc_value ) );
1181                 } else {
1182                         return null;
1183                 }
1184         }
1185
1186         public function startWrite( $code ) {
1187                 if ( $this->readOnly ) {
1188                         return;
1189                 } elseif ( !$code ) {
1190                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
1191                 }
1192
1193                 $this->dbw = wfGetDB( DB_MASTER );
1194
1195                 $this->currentLang = $code;
1196                 $this->batch = array();
1197         }
1198
1199         public function finishWrite() {
1200                 if ( $this->readOnly ) {
1201                         return;
1202                 } elseif ( is_null( $this->currentLang ) ) {
1203                         throw new MWException( __CLASS__ . ': must call startWrite() before finishWrite()' );
1204                 }
1205
1206                 $this->dbw->begin( __METHOD__ );
1207                 try {
1208                         $this->dbw->delete( 'l10n_cache',
1209                                 array( 'lc_lang' => $this->currentLang ), __METHOD__ );
1210                         foreach ( array_chunk( $this->batch, 500 ) as $rows ) {
1211                                 $this->dbw->insert( 'l10n_cache', $rows, __METHOD__ );
1212                         }
1213                         $this->writesDone = true;
1214                 } catch ( DBQueryError $e ) {
1215                         if ( $this->dbw->wasReadOnlyError() ) {
1216                                 $this->readOnly = true; // just avoid site down time
1217                         } else {
1218                                 throw $e;
1219                         }
1220                 }
1221                 $this->dbw->commit( __METHOD__ );
1222
1223                 $this->currentLang = null;
1224                 $this->batch = array();
1225         }
1226
1227         public function set( $key, $value ) {
1228                 if ( $this->readOnly ) {
1229                         return;
1230                 } elseif ( is_null( $this->currentLang ) ) {
1231                         throw new MWException( __CLASS__ . ': must call startWrite() before set()' );
1232                 }
1233
1234                 $this->batch[] = array(
1235                         'lc_lang' => $this->currentLang,
1236                         'lc_key' => $key,
1237                         'lc_value' => $this->dbw->encodeBlob( serialize( $value ) ) );
1238         }
1239 }
1240
1241 /**
1242  * LCStore implementation which stores data as a collection of CDB files in the
1243  * directory given by $wgCacheDirectory. If $wgCacheDirectory is not set, this
1244  * will throw an exception.
1245  *
1246  * Profiling indicates that on Linux, this implementation outperforms MySQL if
1247  * the directory is on a local filesystem and there is ample kernel cache
1248  * space. The performance advantage is greater when the DBA extension is
1249  * available than it is with the PHP port.
1250  *
1251  * See Cdb.php and http://cr.yp.to/cdb.html
1252  */
1253 class LCStoreCDB implements LCStore {
1254         /** @var CdbReader[] */
1255         private $readers;
1256
1257         /** @var CdbWriter */
1258         private $writer;
1259
1260         /** @var string Current language code */
1261         private $currentLang;
1262
1263         /** @var bool|string Cache directory. False if not set */
1264         private $directory;
1265
1266         function __construct( $conf = array() ) {
1267                 global $wgCacheDirectory;
1268
1269                 if ( isset( $conf['directory'] ) ) {
1270                         $this->directory = $conf['directory'];
1271                 } else {
1272                         $this->directory = $wgCacheDirectory;
1273                 }
1274         }
1275
1276         public function get( $code, $key ) {
1277                 if ( !isset( $this->readers[$code] ) ) {
1278                         $fileName = $this->getFileName( $code );
1279
1280                         $this->readers[$code] = false;
1281                         if ( file_exists( $fileName ) ) {
1282                                 try {
1283                                         $this->readers[$code] = CdbReader::open( $fileName );
1284                                 } catch ( CdbException $e ) {
1285                                         wfDebug( __METHOD__ . ": unable to open cdb file for reading\n" );
1286                                 }
1287                         }
1288                 }
1289
1290                 if ( !$this->readers[$code] ) {
1291                         return null;
1292                 } else {
1293                         $value = false;
1294                         try {
1295                                 $value = $this->readers[$code]->get( $key );
1296                         } catch ( CdbException $e ) {
1297                                 wfDebug( __METHOD__ . ": CdbException caught, error message was "
1298                                         . $e->getMessage() . "\n" );
1299                         }
1300                         if ( $value === false ) {
1301                                 return null;
1302                         }
1303
1304                         return unserialize( $value );
1305                 }
1306         }
1307
1308         public function startWrite( $code ) {
1309                 if ( !file_exists( $this->directory ) ) {
1310                         if ( !wfMkdirParents( $this->directory, null, __METHOD__ ) ) {
1311                                 throw new MWException( "Unable to create the localisation store " .
1312                                         "directory \"{$this->directory}\"" );
1313                         }
1314                 }
1315
1316                 // Close reader to stop permission errors on write
1317                 if ( !empty( $this->readers[$code] ) ) {
1318                         $this->readers[$code]->close();
1319                 }
1320
1321                 try {
1322                         $this->writer = CdbWriter::open( $this->getFileName( $code ) );
1323                 } catch ( CdbException $e ) {
1324                         throw new MWException( $e->getMessage() );
1325                 }
1326                 $this->currentLang = $code;
1327         }
1328
1329         public function finishWrite() {
1330                 // Close the writer
1331                 try {
1332                         $this->writer->close();
1333                 } catch ( CdbException $e ) {
1334                         throw new MWException( $e->getMessage() );
1335                 }
1336                 $this->writer = null;
1337                 unset( $this->readers[$this->currentLang] );
1338                 $this->currentLang = null;
1339         }
1340
1341         public function set( $key, $value ) {
1342                 if ( is_null( $this->writer ) ) {
1343                         throw new MWException( __CLASS__ . ': must call startWrite() before calling set()' );
1344                 }
1345                 try {
1346                         $this->writer->set( $key, serialize( $value ) );
1347                 } catch ( CdbException $e ) {
1348                         throw new MWException( $e->getMessage() );
1349                 }
1350         }
1351
1352         protected function getFileName( $code ) {
1353                 if ( strval( $code ) === '' || strpos( $code, '/' ) !== false ) {
1354                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
1355                 }
1356
1357                 return "{$this->directory}/l10n_cache-$code.cdb";
1358         }
1359 }
1360
1361 /**
1362  * Null store backend, used to avoid DB errors during install
1363  */
1364 class LCStoreNull implements LCStore {
1365         public function get( $code, $key ) {
1366                 return null;
1367         }
1368
1369         public function startWrite( $code ) {
1370         }
1371
1372         public function finishWrite() {
1373         }
1374
1375         public function set( $key, $value ) {
1376         }
1377 }
1378
1379 /**
1380  * A localisation cache optimised for loading large amounts of data for many
1381  * languages. Used by rebuildLocalisationCache.php.
1382  */
1383 class LocalisationCacheBulkLoad extends LocalisationCache {
1384         /**
1385          * A cache of the contents of data files.
1386          * Core files are serialized to avoid using ~1GB of RAM during a recache.
1387          */
1388         private $fileCache = array();
1389
1390         /**
1391          * Most recently used languages. Uses the linked-list aspect of PHP hashtables
1392          * to keep the most recently used language codes at the end of the array, and
1393          * the language codes that are ready to be deleted at the beginning.
1394          */
1395         private $mruLangs = array();
1396
1397         /**
1398          * Maximum number of languages that may be loaded into $this->data
1399          */
1400         private $maxLoadedLangs = 10;
1401
1402         /**
1403          * @param string $fileName
1404          * @param string $fileType
1405          * @return array|mixed
1406          */
1407         protected function readPHPFile( $fileName, $fileType ) {
1408                 $serialize = $fileType === 'core';
1409                 if ( !isset( $this->fileCache[$fileName][$fileType] ) ) {
1410                         $data = parent::readPHPFile( $fileName, $fileType );
1411
1412                         if ( $serialize ) {
1413                                 $encData = serialize( $data );
1414                         } else {
1415                                 $encData = $data;
1416                         }
1417
1418                         $this->fileCache[$fileName][$fileType] = $encData;
1419
1420                         return $data;
1421                 } elseif ( $serialize ) {
1422                         return unserialize( $this->fileCache[$fileName][$fileType] );
1423                 } else {
1424                         return $this->fileCache[$fileName][$fileType];
1425                 }
1426         }
1427
1428         /**
1429          * @param string $code
1430          * @param string $key
1431          * @return mixed
1432          */
1433         public function getItem( $code, $key ) {
1434                 unset( $this->mruLangs[$code] );
1435                 $this->mruLangs[$code] = true;
1436
1437                 return parent::getItem( $code, $key );
1438         }
1439
1440         /**
1441          * @param string $code
1442          * @param string $key
1443          * @param string $subkey
1444          * @return mixed
1445          */
1446         public function getSubitem( $code, $key, $subkey ) {
1447                 unset( $this->mruLangs[$code] );
1448                 $this->mruLangs[$code] = true;
1449
1450                 return parent::getSubitem( $code, $key, $subkey );
1451         }
1452
1453         /**
1454          * @param string $code
1455          */
1456         public function recache( $code ) {
1457                 parent::recache( $code );
1458                 unset( $this->mruLangs[$code] );
1459                 $this->mruLangs[$code] = true;
1460                 $this->trimCache();
1461         }
1462
1463         /**
1464          * @param string $code
1465          */
1466         public function unload( $code ) {
1467                 unset( $this->mruLangs[$code] );
1468                 parent::unload( $code );
1469         }
1470
1471         /**
1472          * Unload cached languages until there are less than $this->maxLoadedLangs
1473          */
1474         protected function trimCache() {
1475                 while ( count( $this->data ) > $this->maxLoadedLangs && count( $this->mruLangs ) ) {
1476                         reset( $this->mruLangs );
1477                         $code = key( $this->mruLangs );
1478                         wfDebug( __METHOD__ . ": unloading $code\n" );
1479                         $this->unload( $code );
1480                 }
1481         }
1482 }