includes/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         var $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         var $manualRecache = false;
  47
  48         /**
  49          * True to treat all files as expired until they are regenerated by this object.
  50          */
  51         var $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         var $data = array();
  60
  61         /**
  62          * The persistent store object. An instance of LCStore.
  63          *
  64          * @var LCStore
  65          */
  66         var $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         var $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         var $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         var $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         var $shallowFallbacks = array();
  96
  97         /**
  98          * An array where the keys are codes that have been recached by this instance.
  99          */
 100         var $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', 'namespaceAliases',
 110                 'dateFormats', 'datePreferences', 'datePreferenceMigrationMap',
 111                 'defaultDateFormat', 'extraUserToggles', 'specialPageAliases',
 112                 'imageFiles', 'preloadedMessages', 'namespaceGenderAliases',
 113                 'digitGroupingPattern', 'pluralRules'
 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', 'pluralRules'
 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         var $pluralRules = null;
 162
 163         var $mergeableKeys = null;
 164
 165         /**
 166          * Constructor.
 167          * For constructor parameters, see the documentation in DefaultSettings.php
 168          * for $wgLocalisationCacheConf.
 169          *
 170          * @param $conf Array
 171          */
 172         function __construct( $conf ) {
 173                 global $wgCacheDirectory;
 174
 175                 $this->conf = $conf;
 176                 $storeConf = array();
 177                 if ( !empty( $conf['storeClass'] ) ) {
 178                         $storeClass = $conf['storeClass'];
 179                 } else {
 180                         switch ( $conf['store'] ) {
 181                                 case 'files':
 182                                 case 'file':
 183                                         $storeClass = 'LCStore_CDB';
 184                                         break;
 185                                 case 'db':
 186                                         $storeClass = 'LCStore_DB';
 187                                         break;
 188                                 case 'accel':
 189                                         $storeClass = 'LCStore_Accel';
 190                                         break;
 191                                 case 'detect':
 192                                         $storeClass = $wgCacheDirectory ? 'LCStore_CDB' : 'LCStore_DB';
 193                                         break;
 194                                 default:
 195                                         throw new MWException(
 196                                                 'Please set $wgLocalisationCacheConf[\'store\'] to something sensible.' );
 197                         }
 198                 }
 199
 200                 wfDebug( get_class( $this ) . ": using store $storeClass\n" );
 201                 if ( !empty( $conf['storeDirectory'] ) ) {
 202                         $storeConf['directory'] = $conf['storeDirectory'];
 203                 }
 204
 205                 $this->store = new $storeClass( $storeConf );
 206                 foreach ( array( 'manualRecache', 'forceRecache' ) as $var ) {
 207                         if ( isset( $conf[$var] ) ) {
 208                                 $this->$var = $conf[$var];
 209                         }
 210                 }
 211         }
 212
 213         /**
 214          * Returns true if the given key is mergeable, that is, if it is an associative
 215          * array which can be merged through a fallback sequence.
 216          * @param $key
 217          * @return bool
 218          */
 219         public function isMergeableKey( $key ) {
 220                 if ( $this->mergeableKeys === null ) {
 221                         $this->mergeableKeys = array_flip( array_merge(
 222                                 self::$mergeableMapKeys,
 223                                 self::$mergeableListKeys,
 224                                 self::$mergeableAliasListKeys,
 225                                 self::$optionalMergeKeys,
 226                                 self::$magicWordKeys
 227                         ) );
 228                 }
 229                 return isset( $this->mergeableKeys[$key] );
 230         }
 231
 232         /**
 233          * Get a cache item.
 234          *
 235          * Warning: this may be slow for split items (messages), since it will
 236          * need to fetch all of the subitems from the cache individually.
 237          * @param $code
 238          * @param $key
 239          * @return mixed
 240          */
 241         public function getItem( $code, $key ) {
 242                 if ( !isset( $this->loadedItems[$code][$key] ) ) {
 243                         wfProfileIn( __METHOD__ . '-load' );
 244                         $this->loadItem( $code, $key );
 245                         wfProfileOut( __METHOD__ . '-load' );
 246                 }
 247
 248                 if ( $key === 'fallback' && isset( $this->shallowFallbacks[$code] ) ) {
 249                         return $this->shallowFallbacks[$code];
 250                 }
 251
 252                 return $this->data[$code][$key];
 253         }
 254
 255         /**
 256          * Get a subitem, for instance a single message for a given language.
 257          * @param $code
 258          * @param $key
 259          * @param $subkey
 260          * @return null
 261          */
 262         public function getSubitem( $code, $key, $subkey ) {
 263                 if ( !isset( $this->loadedSubitems[$code][$key][$subkey] ) &&
 264                          !isset( $this->loadedItems[$code][$key] ) ) {
 265                         wfProfileIn( __METHOD__ . '-load' );
 266                         $this->loadSubitem( $code, $key, $subkey );
 267                         wfProfileOut( __METHOD__ . '-load' );
 268                 }
 269
 270                 if ( isset( $this->data[$code][$key][$subkey] ) ) {
 271                         return $this->data[$code][$key][$subkey];
 272                 } else {
 273                         return null;
 274                 }
 275         }
 276
 277         /**
 278          * Get the list of subitem keys for a given item.
 279          *
 280          * This is faster than array_keys($lc->getItem(...)) for the items listed in
 281          * self::$splitKeys.
 282          *
 283          * Will return null if the item is not found, or false if the item is not an
 284          * array.
 285          * @param $code
 286          * @param $key
 287          * @return bool|null|string
 288          */
 289         public function getSubitemList( $code, $key ) {
 290                 if ( in_array( $key, self::$splitKeys ) ) {
 291                         return $this->getSubitem( $code, 'list', $key );
 292                 } else {
 293                         $item = $this->getItem( $code, $key );
 294                         if ( is_array( $item ) ) {
 295                                 return array_keys( $item );
 296                         } else {
 297                                 return false;
 298                         }
 299                 }
 300         }
 301
 302         /**
 303          * Load an item into the cache.
 304          * @param $code
 305          * @param $key
 306          */
 307         protected function loadItem( $code, $key ) {
 308                 if ( !isset( $this->initialisedLangs[$code] ) ) {
 309                         $this->initLanguage( $code );
 310                 }
 311
 312                 // Check to see if initLanguage() loaded it for us
 313                 if ( isset( $this->loadedItems[$code][$key] ) ) {
 314                         return;
 315                 }
 316
 317                 if ( isset( $this->shallowFallbacks[$code] ) ) {
 318                         $this->loadItem( $this->shallowFallbacks[$code], $key );
 319                         return;
 320                 }
 321
 322                 if ( in_array( $key, self::$splitKeys ) ) {
 323                         $subkeyList = $this->getSubitem( $code, 'list', $key );
 324                         foreach ( $subkeyList as $subkey ) {
 325                                 if ( isset( $this->data[$code][$key][$subkey] ) ) {
 326                                         continue;
 327                                 }
 328                                 $this->data[$code][$key][$subkey] = $this->getSubitem( $code, $key, $subkey );
 329                         }
 330                 } else {
 331                         $this->data[$code][$key] = $this->store->get( $code, $key );
 332                 }
 333
 334                 $this->loadedItems[$code][$key] = true;
 335         }
 336
 337         /**
 338          * Load a subitem into the cache
 339          * @param $code
 340          * @param $key
 341          * @param $subkey
 342          * @return
 343          */
 344         protected function loadSubitem( $code, $key, $subkey ) {
 345                 if ( !in_array( $key, self::$splitKeys ) ) {
 346                         $this->loadItem( $code, $key );
 347                         return;
 348                 }
 349
 350                 if ( !isset( $this->initialisedLangs[$code] ) ) {
 351                         $this->initLanguage( $code );
 352                 }
 353
 354                 // Check to see if initLanguage() loaded it for us
 355                 if ( isset( $this->loadedItems[$code][$key] ) ||
 356                          isset( $this->loadedSubitems[$code][$key][$subkey] ) ) {
 357                         return;
 358                 }
 359
 360                 if ( isset( $this->shallowFallbacks[$code] ) ) {
 361                         $this->loadSubitem( $this->shallowFallbacks[$code], $key, $subkey );
 362                         return;
 363                 }
 364
 365                 $value = $this->store->get( $code, "$key:$subkey" );
 366                 $this->data[$code][$key][$subkey] = $value;
 367                 $this->loadedSubitems[$code][$key][$subkey] = true;
 368         }
 369
 370         /**
 371          * Returns true if the cache identified by $code is missing or expired.
 372          * @return bool
 373          */
 374         public function isExpired( $code ) {
 375                 if ( $this->forceRecache && !isset( $this->recachedLangs[$code] ) ) {
 376                         wfDebug( __METHOD__ . "($code): forced reload\n" );
 377                         return true;
 378                 }
 379
 380                 $deps = $this->store->get( $code, 'deps' );
 381                 $keys = $this->store->get( $code, 'list', 'messages' );
 382                 $preload = $this->store->get( $code, 'preload' );
 383                 // Different keys may expire separately, at least in LCStore_Accel
 384                 if ( $deps === null || $keys === null || $preload === null ) {
 385                         wfDebug( __METHOD__ . "($code): cache missing, need to make one\n" );
 386                         return true;
 387                 }
 388
 389                 foreach ( $deps as $dep ) {
 390                         // Because we're unserializing stuff from cache, we
 391                         // could receive objects of classes that don't exist
 392                         // anymore (e.g. uninstalled extensions)
 393                         // When this happens, always expire the cache
 394                         if ( !$dep instanceof CacheDependency || $dep->isExpired() ) {
 395                                 wfDebug( __METHOD__ . "($code): cache for $code expired due to " .
 396                                         get_class( $dep ) . "\n" );
 397                                 return true;
 398                         }
 399                 }
 400
 401                 return false;
 402         }
 403
 404         /**
 405          * Initialise a language in this object. Rebuild the cache if necessary.
 406          * @param $code
 407          */
 408         protected function initLanguage( $code ) {
 409                 if ( isset( $this->initialisedLangs[$code] ) ) {
 410                         return;
 411                 }
 412
 413                 $this->initialisedLangs[$code] = true;
 414
 415                 # If the code is of the wrong form for a Messages*.php file, do a shallow fallback
 416                 if ( !Language::isValidBuiltInCode( $code ) ) {
 417                         $this->initShallowFallback( $code, 'en' );
 418                         return;
 419                 }
 420
 421                 # Recache the data if necessary
 422                 if ( !$this->manualRecache && $this->isExpired( $code ) ) {
 423                         if ( file_exists( Language::getMessagesFileName( $code ) ) ) {
 424                                 $this->recache( $code );
 425                         } elseif ( $code === 'en' ) {
 426                                 throw new MWException( 'MessagesEn.php is missing.' );
 427                         } else {
 428                                 $this->initShallowFallback( $code, 'en' );
 429                         }
 430                         return;
 431                 }
 432
 433                 # Preload some stuff
 434                 $preload = $this->getItem( $code, 'preload' );
 435                 if ( $preload === null ) {
 436                         if ( $this->manualRecache ) {
 437                                 // No Messages*.php file. Do shallow fallback to en.
 438                                 if ( $code === 'en' ) {
 439                                         throw new MWException( 'No localisation cache found for English. ' .
 440                                                 'Please run maintenance/rebuildLocalisationCache.php.' );
 441                                 }
 442                                 $this->initShallowFallback( $code, 'en' );
 443                                 return;
 444                         } else {
 445                                 throw new MWException( 'Invalid or missing localisation cache.' );
 446                         }
 447                 }
 448                 $this->data[$code] = $preload;
 449                 foreach ( $preload as $key => $item ) {
 450                         if ( in_array( $key, self::$splitKeys ) ) {
 451                                 foreach ( $item as $subkey => $subitem ) {
 452                                         $this->loadedSubitems[$code][$key][$subkey] = true;
 453                                 }
 454                         } else {
 455                                 $this->loadedItems[$code][$key] = true;
 456                         }
 457                 }
 458         }
 459
 460         /**
 461          * Create a fallback from one language to another, without creating a
 462          * complete persistent cache.
 463          * @param $primaryCode
 464          * @param $fallbackCode
 465          */
 466         public function initShallowFallback( $primaryCode, $fallbackCode ) {
 467                 $this->data[$primaryCode] =& $this->data[$fallbackCode];
 468                 $this->loadedItems[$primaryCode] =& $this->loadedItems[$fallbackCode];
 469                 $this->loadedSubitems[$primaryCode] =& $this->loadedSubitems[$fallbackCode];
 470                 $this->shallowFallbacks[$primaryCode] = $fallbackCode;
 471         }
 472
 473         /**
 474          * Read a PHP file containing localisation data.
 475          * @param $_fileName
 476          * @param $_fileType
 477          * @return array
 478          */
 479         protected function readPHPFile( $_fileName, $_fileType ) {
 480                 // Disable APC caching
 481                 $_apcEnabled = ini_set( 'apc.cache_by_default', '0' );
 482                 include( $_fileName );
 483                 ini_set( 'apc.cache_by_default', $_apcEnabled );
 484
 485                 if ( $_fileType == 'core' || $_fileType == 'extension' ) {
 486                         $data = compact( self::$allKeys );
 487                 } elseif ( $_fileType == 'aliases' ) {
 488                         $data = compact( 'aliases' );
 489                 } else {
 490                         throw new MWException( __METHOD__ . ": Invalid file type: $_fileType" );
 491                 }
 492                 return $data;
 493         }
 494
 495         /**
 496          * Get the compiled plural rules for a given language from the XML files.
 497          * @since 1.20
 498          */
 499         public function getCompiledPluralRules( $code ) {
 500                 $rules = $this->getPluralRules( $code );
 501                 try {
 502                         $compiledRules = CLDRPluralRuleEvaluator::compile( $rules );
 503                 } catch( CLDRPluralRuleError $e ) {
 504                         wfDebugLog( 'l10n', $e->getMessage() . "\n" );
 505                         return array();
 506                 }
 507                 return $compiledRules;
 508         }
 509
 510         /**
 511          * Get the plural rules for a given language from the XML files.
 512          * Cached.
 513          * @since 1.20
 514          */
 515         public function getPluralRules( $code ) {
 516                 if ( $this->pluralRules === null ) {
 517                         $cldrPlural = __DIR__ . "/../languages/data/plurals.xml";
 518                         $mwPlural = __DIR__ . "/../languages/data/plurals-mediawiki.xml";
 519                         // Load CLDR plural rules
 520                         $this->loadPluralFile( $cldrPlural );
 521                         if ( file_exists( $mwPlural ) ) {
 522                                 // Override or extend
 523                                 $this->loadPluralFile( $mwPlural );
 524                         }
 525                 }
 526                 if ( !isset( $this->pluralRules[$code] ) ) {
 527                         return array();
 528                 } else {
 529                         return $this->pluralRules[$code];
 530                 }
 531         }
 532
 533         /**
 534          * Load a plural XML file with the given filename, compile the relevant
 535          * rules, and save the compiled rules in a process-local cache.
 536          */
 537         private function loadPluralFile( $fileName ) {
 538                 $doc = new DOMDocument;
 539                 $doc->load( $fileName );
 540                 $rulesets = $doc->getElementsByTagName( "pluralRules" );
 541                 foreach ( $rulesets as $ruleset ) {
 542                         $codes = $ruleset->getAttribute( 'locales' );
 543                         $rules = array();
 544                         $ruleElements = $ruleset->getElementsByTagName( "pluralRule" );
 545                         foreach ( $ruleElements as $elt ) {
 546                                 $rules[] = $elt->nodeValue;
 547                         }
 548                         foreach ( explode( ' ', $codes ) as $code ) {
 549                                 $this->pluralRules[$code] = $rules;
 550                         }
 551                 }
 552         }
 553
 554         /**
 555          * Merge two localisation values, a primary and a fallback, overwriting the
 556          * primary value in place.
 557          * @param $key
 558          * @param $value
 559          * @param $fallbackValue
 560          */
 561         protected function mergeItem( $key, &$value, $fallbackValue ) {
 562                 if ( !is_null( $value ) ) {
 563                         if ( !is_null( $fallbackValue ) ) {
 564                                 if ( in_array( $key, self::$mergeableMapKeys ) ) {
 565                                         $value = $value + $fallbackValue;
 566                                 } elseif ( in_array( $key, self::$mergeableListKeys ) ) {
 567                                         $value = array_unique( array_merge( $fallbackValue, $value ) );
 568                                 } elseif ( in_array( $key, self::$mergeableAliasListKeys ) ) {
 569                                         $value = array_merge_recursive( $value, $fallbackValue );
 570                                 } elseif ( in_array( $key, self::$optionalMergeKeys ) ) {
 571                                         if ( !empty( $value['inherit'] ) )  {
 572                                                 $value = array_merge( $fallbackValue, $value );
 573                                         }
 574
 575                                         if ( isset( $value['inherit'] ) ) {
 576                                                 unset( $value['inherit'] );
 577                                         }
 578                                 } elseif ( in_array( $key, self::$magicWordKeys ) ) {
 579                                         $this->mergeMagicWords( $value, $fallbackValue );
 580                                 }
 581                         }
 582                 } else {
 583                         $value = $fallbackValue;
 584                 }
 585         }
 586
 587         /**
 588          * @param $value
 589          * @param $fallbackValue
 590          */
 591         protected function mergeMagicWords( &$value, $fallbackValue ) {
 592                 foreach ( $fallbackValue as $magicName => $fallbackInfo ) {
 593                         if ( !isset( $value[$magicName] ) ) {
 594                                 $value[$magicName] = $fallbackInfo;
 595                         } else {
 596                                 $oldSynonyms = array_slice( $fallbackInfo, 1 );
 597                                 $newSynonyms = array_slice( $value[$magicName], 1 );
 598                                 $synonyms = array_values( array_unique( array_merge(
 599                                         $newSynonyms, $oldSynonyms ) ) );
 600                                 $value[$magicName] = array_merge( array( $fallbackInfo[0] ), $synonyms );
 601                         }
 602                 }
 603         }
 604
 605         /**
 606          * Given an array mapping language code to localisation value, such as is
 607          * found in extension *.i18n.php files, iterate through a fallback sequence
 608          * to merge the given data with an existing primary value.
 609          *
 610          * Returns true if any data from the extension array was used, false
 611          * otherwise.
 612          * @param $codeSequence
 613          * @param $key
 614          * @param $value
 615          * @param $fallbackValue
 616          * @return bool
 617          */
 618         protected function mergeExtensionItem( $codeSequence, $key, &$value, $fallbackValue ) {
 619                 $used = false;
 620                 foreach ( $codeSequence as $code ) {
 621                         if ( isset( $fallbackValue[$code] ) ) {
 622                                 $this->mergeItem( $key, $value, $fallbackValue[$code] );
 623                                 $used = true;
 624                         }
 625                 }
 626
 627                 return $used;
 628         }
 629
 630         /**
 631          * Load localisation data for a given language for both core and extensions
 632          * and save it to the persistent cache store and the process cache
 633          * @param $code
 634          */
 635         public function recache( $code ) {
 636                 global $wgExtensionMessagesFiles;
 637                 wfProfileIn( __METHOD__ );
 638
 639                 if ( !$code ) {
 640                         throw new MWException( "Invalid language code requested" );
 641                 }
 642                 $this->recachedLangs[$code] = true;
 643
 644                 # Initial values
 645                 $initialData = array_combine(
 646                         self::$allKeys,
 647                         array_fill( 0, count( self::$allKeys ), null ) );
 648                 $coreData = $initialData;
 649                 $deps = array();
 650
 651                 # Load the primary localisation from the source file
 652                 $fileName = Language::getMessagesFileName( $code );
 653                 if ( !file_exists( $fileName ) ) {
 654                         wfDebug( __METHOD__ . ": no localisation file for $code, using fallback to en\n" );
 655                         $coreData['fallback'] = 'en';
 656                 } else {
 657                         $deps[] = new FileDependency( $fileName );
 658                         $data = $this->readPHPFile( $fileName, 'core' );
 659                         wfDebug( __METHOD__ . ": got localisation for $code from source\n" );
 660
 661                         # Merge primary localisation
 662                         foreach ( $data as $key => $value ) {
 663                                 $this->mergeItem( $key, $coreData[$key], $value );
 664                         }
 665
 666                 }
 667
 668                 # Fill in the fallback if it's not there already
 669                 if ( is_null( $coreData['fallback'] ) ) {
 670                         $coreData['fallback'] = $code === 'en' ? false : 'en';
 671                 }
 672                 if ( $coreData['fallback'] === false ) {
 673                         $coreData['fallbackSequence'] = array();
 674                 } else {
 675                         $coreData['fallbackSequence'] = array_map( 'trim', explode( ',', $coreData['fallback'] ) );
 676                         $len = count( $coreData['fallbackSequence'] );
 677
 678                         # Ensure that the sequence ends at en
 679                         if ( $coreData['fallbackSequence'][$len - 1] !== 'en' ) {
 680                                 $coreData['fallbackSequence'][] = 'en';
 681                         }
 682
 683                         # Load the fallback localisation item by item and merge it
 684                         foreach ( $coreData['fallbackSequence'] as $fbCode ) {
 685                                 # Load the secondary localisation from the source file to
 686                                 # avoid infinite cycles on cyclic fallbacks
 687                                 $fbFilename = Language::getMessagesFileName( $fbCode );
 688
 689                                 if ( !file_exists( $fbFilename ) ) {
 690                                         continue;
 691                                 }
 692
 693                                 $deps[] = new FileDependency( $fbFilename );
 694                                 $fbData = $this->readPHPFile( $fbFilename, 'core' );
 695
 696                                 foreach ( self::$allKeys as $key ) {
 697                                         if ( !isset( $fbData[$key] ) ) {
 698                                                 continue;
 699                                         }
 700
 701                                         if ( is_null( $coreData[$key] ) || $this->isMergeableKey( $key ) ) {
 702                                                 $this->mergeItem( $key, $coreData[$key], $fbData[$key] );
 703                                         }
 704                                 }
 705                         }
 706                 }
 707
 708                 $codeSequence = array_merge( array( $code ), $coreData['fallbackSequence'] );
 709
 710                 # Load the extension localisations
 711                 # This is done after the core because we know the fallback sequence now.
 712                 # But it has a higher precedence for merging so that we can support things
 713                 # like site-specific message overrides.
 714                 $allData = $initialData;
 715                 foreach ( $wgExtensionMessagesFiles as $fileName ) {
 716                         $data = $this->readPHPFile( $fileName, 'extension' );
 717                         $used = false;
 718
 719                         foreach ( $data as $key => $item ) {
 720                                 if ( $this->mergeExtensionItem( $codeSequence, $key, $allData[$key], $item ) ) {
 721                                         $used = true;
 722                                 }
 723                         }
 724
 725                         if ( $used ) {
 726                                 $deps[] = new FileDependency( $fileName );
 727                         }
 728                 }
 729
 730                 # Merge core data into extension data
 731                 foreach ( $coreData as $key => $item ) {
 732                         $this->mergeItem( $key, $allData[$key], $item );
 733                 }
 734
 735                 # Add cache dependencies for any referenced globals
 736                 $deps['wgExtensionMessagesFiles'] = new GlobalDependency( 'wgExtensionMessagesFiles' );
 737                 $deps['version'] = new ConstantDependency( 'MW_LC_VERSION' );
 738
 739                 # Add dependencies to the cache entry
 740                 $allData['deps'] = $deps;
 741
 742                 # Replace spaces with underscores in namespace names
 743                 $allData['namespaceNames'] = str_replace( ' ', '_', $allData['namespaceNames'] );
 744
 745                 # And do the same for special page aliases. $page is an array.
 746                 foreach ( $allData['specialPageAliases'] as &$page ) {
 747                         $page = str_replace( ' ', '_', $page );
 748                 }
 749                 # Decouple the reference to prevent accidental damage
 750                 unset( $page );
 751
 752                 # Set the list keys
 753                 $allData['list'] = array();
 754                 foreach ( self::$splitKeys as $key ) {
 755                         $allData['list'][$key] = array_keys( $allData[$key] );
 756                 }
 757                 # Load CLDR plural rules for JavaScript
 758                 $allData['pluralRules'] = $this->getPluralRules( $code );
 759                 # And for PHP
 760                 $allData['compiledPluralRules'] = $this->getCompiledPluralRules( $code );
 761                 # Run hooks
 762                 wfRunHooks( 'LocalisationCacheRecache', array( $this, $code, &$allData ) );
 763
 764                 if ( is_null( $allData['namespaceNames'] ) ) {
 765                         throw new MWException( __METHOD__ . ': Localisation data failed sanity check! ' .
 766                                 'Check that your languages/messages/MessagesEn.php file is intact.' );
 767                 }
 768
 769                 # Set the preload key
 770                 $allData['preload'] = $this->buildPreload( $allData );
 771
 772                 # Save to the process cache and register the items loaded
 773                 $this->data[$code] = $allData;
 774                 foreach ( $allData as $key => $item ) {
 775                         $this->loadedItems[$code][$key] = true;
 776                 }
 777
 778                 # Save to the persistent cache
 779                 $this->store->startWrite( $code );
 780                 foreach ( $allData as $key => $value ) {
 781                         if ( in_array( $key, self::$splitKeys ) ) {
 782                                 foreach ( $value as $subkey => $subvalue ) {
 783                                         $this->store->set( "$key:$subkey", $subvalue );
 784                                 }
 785                         } else {
 786                                 $this->store->set( $key, $value );
 787                         }
 788                 }
 789                 $this->store->finishWrite();
 790
 791                 # Clear out the MessageBlobStore
 792                 # HACK: If using a null (i.e. disabled) storage backend, we
 793                 # can't write to the MessageBlobStore either
 794                 if ( !$this->store instanceof LCStore_Null ) {
 795                         MessageBlobStore::clear();
 796                 }
 797
 798                 wfProfileOut( __METHOD__ );
 799         }
 800
 801         /**
 802          * Build the preload item from the given pre-cache data.
 803          *
 804          * The preload item will be loaded automatically, improving performance
 805          * for the commonly-requested items it contains.
 806          * @param $data
 807          * @return array
 808          */
 809         protected function buildPreload( $data ) {
 810                 $preload = array( 'messages' => array() );
 811                 foreach ( self::$preloadedKeys as $key ) {
 812                         $preload[$key] = $data[$key];
 813                 }
 814
 815                 foreach ( $data['preloadedMessages'] as $subkey ) {
 816                         if ( isset( $data['messages'][$subkey] ) ) {
 817                                 $subitem = $data['messages'][$subkey];
 818                         } else {
 819                                 $subitem = null;
 820                         }
 821                         $preload['messages'][$subkey] = $subitem;
 822                 }
 823
 824                 return $preload;
 825         }
 826
 827         /**
 828          * Unload the data for a given language from the object cache.
 829          * Reduces memory usage.
 830          * @param $code
 831          */
 832         public function unload( $code ) {
 833                 unset( $this->data[$code] );
 834                 unset( $this->loadedItems[$code] );
 835                 unset( $this->loadedSubitems[$code] );
 836                 unset( $this->initialisedLangs[$code] );
 837
 838                 foreach ( $this->shallowFallbacks as $shallowCode => $fbCode ) {
 839                         if ( $fbCode === $code ) {
 840                                 $this->unload( $shallowCode );
 841                         }
 842                 }
 843         }
 844
 845         /**
 846          * Unload all data
 847          */
 848         public function unloadAll() {
 849                 foreach ( $this->initialisedLangs as $lang => $unused ) {
 850                         $this->unload( $lang );
 851                 }
 852         }
 853
 854         /**
 855          * Disable the storage backend
 856          */
 857         public function disableBackend() {
 858                 $this->store = new LCStore_Null;
 859                 $this->manualRecache = false;
 860         }
 861 }
 862
 863 /**
 864  * Interface for the persistence layer of LocalisationCache.
 865  *
 866  * The persistence layer is two-level hierarchical cache. The first level
 867  * is the language, the second level is the item or subitem.
 868  *
 869  * Since the data for a whole language is rebuilt in one operation, it needs
 870  * to have a fast and atomic method for deleting or replacing all of the
 871  * current data for a given language. The interface reflects this bulk update
 872  * operation. Callers writing to the cache must first call startWrite(), then
 873  * will call set() a couple of thousand times, then will call finishWrite()
 874  * to commit the operation. When finishWrite() is called, the cache is
 875  * expected to delete all data previously stored for that language.
 876  *
 877  * The values stored are PHP variables suitable for serialize(). Implementations
 878  * of LCStore are responsible for serializing and unserializing.
 879  */
 880 interface LCStore {
 881         /**
 882          * Get a value.
 883          * @param $code string Language code
 884          * @param $key string Cache key
 885          */
 886         function get( $code, $key );
 887
 888         /**
 889          * Start a write transaction.
 890          * @param $code Language code
 891          */
 892         function startWrite( $code );
 893
 894         /**
 895          * Finish a write transaction.
 896          */
 897         function finishWrite();
 898
 899         /**
 900          * Set a key to a given value. startWrite() must be called before this
 901          * is called, and finishWrite() must be called afterwards.
 902          * @param $key
 903          * @param $value
 904          */
 905         function set( $key, $value );
 906 }
 907
 908 /**
 909  * LCStore implementation which uses PHP accelerator to store data.
 910  * This will work if one of XCache, WinCache or APC cacher is configured.
 911  * (See ObjectCache.php)
 912  */
 913 class LCStore_Accel implements LCStore {
 914         var $currentLang;
 915         var $keys;
 916
 917         public function __construct() {
 918                 $this->cache = wfGetCache( CACHE_ACCEL );
 919         }
 920
 921         public function get( $code, $key ) {
 922                 $k = wfMemcKey( 'l10n', $code, 'k', $key );
 923                 $r = $this->cache->get( $k );
 924                 return $r === false ? null : $r;
 925         }
 926
 927         public function startWrite( $code ) {
 928                 $k = wfMemcKey( 'l10n', $code, 'l' );
 929                 $keys = $this->cache->get( $k );
 930                 if ( $keys ) {
 931                         foreach ( $keys as $k ) {
 932                                 $this->cache->delete( $k );
 933                         }
 934                 }
 935                 $this->currentLang = $code;
 936                 $this->keys = array();
 937         }
 938
 939         public function finishWrite() {
 940                 if ( $this->currentLang ) {
 941                         $k = wfMemcKey( 'l10n', $this->currentLang, 'l' );
 942                         $this->cache->set( $k, array_keys( $this->keys ) );
 943                 }
 944                 $this->currentLang = null;
 945                 $this->keys = array();
 946         }
 947
 948         public function set( $key, $value ) {
 949                 if ( $this->currentLang ) {
 950                         $k = wfMemcKey( 'l10n', $this->currentLang, 'k', $key );
 951                         $this->keys[$k] = true;
 952                         $this->cache->set( $k, $value );
 953                 }
 954         }
 955 }
 956
 957 /**
 958  * LCStore implementation which uses the standard DB functions to store data.
 959  * This will work on any MediaWiki installation.
 960  */
 961 class LCStore_DB implements LCStore {
 962         var $currentLang;
 963         var $writesDone = false;
 964
 965         /**
 966          * @var DatabaseBase
 967          */
 968         var $dbw;
 969         var $batch;
 970         var $readOnly = false;
 971
 972         public function get( $code, $key ) {
 973                 if ( $this->writesDone ) {
 974                         $db = wfGetDB( DB_MASTER );
 975                 } else {
 976                         $db = wfGetDB( DB_SLAVE );
 977                 }
 978                 $row = $db->selectRow( 'l10n_cache', array( 'lc_value' ),
 979                         array( 'lc_lang' => $code, 'lc_key' => $key ), __METHOD__ );
 980                 if ( $row ) {
 981                         return unserialize( $row->lc_value );
 982                 } else {
 983                         return null;
 984                 }
 985         }
 986
 987         public function startWrite( $code ) {
 988                 if ( $this->readOnly ) {
 989                         return;
 990                 }
 991
 992                 if ( !$code ) {
 993                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
 994                 }
 995
 996                 $this->dbw = wfGetDB( DB_MASTER );
 997                 try {
 998                         $this->dbw->begin( __METHOD__ );
 999                         $this->dbw->delete( 'l10n_cache', array( 'lc_lang' => $code ), __METHOD__ );
1000                 } catch ( DBQueryError $e ) {
1001                         if ( $this->dbw->wasReadOnlyError() ) {
1002                                 $this->readOnly = true;
1003                                 $this->dbw->rollback( __METHOD__ );
1004                                 $this->dbw->ignoreErrors( false );
1005                                 return;
1006                         } else {
1007                                 throw $e;
1008                         }
1009                 }
1010
1011                 $this->currentLang = $code;
1012                 $this->batch = array();
1013         }
1014
1015         public function finishWrite() {
1016                 if ( $this->readOnly ) {
1017                         return;
1018                 }
1019
1020                 if ( $this->batch ) {
1021                         $this->dbw->insert( 'l10n_cache', $this->batch, __METHOD__ );
1022                 }
1023
1024                 $this->dbw->commit( __METHOD__ );
1025                 $this->currentLang = null;
1026                 $this->dbw = null;
1027                 $this->batch = array();
1028                 $this->writesDone = true;
1029         }
1030
1031         public function set( $key, $value ) {
1032                 if ( $this->readOnly ) {
1033                         return;
1034                 }
1035
1036                 if ( is_null( $this->currentLang ) ) {
1037                         throw new MWException( __CLASS__ . ': must call startWrite() before calling set()' );
1038                 }
1039
1040                 $this->batch[] = array(
1041                         'lc_lang' => $this->currentLang,
1042                         'lc_key' => $key,
1043                         'lc_value' => serialize( $value ) );
1044
1045                 if ( count( $this->batch ) >= 100 ) {
1046                         $this->dbw->insert( 'l10n_cache', $this->batch, __METHOD__ );
1047                         $this->batch = array();
1048                 }
1049         }
1050 }
1051
1052 /**
1053  * LCStore implementation which stores data as a collection of CDB files in the
1054  * directory given by $wgCacheDirectory. If $wgCacheDirectory is not set, this
1055  * will throw an exception.
1056  *
1057  * Profiling indicates that on Linux, this implementation outperforms MySQL if
1058  * the directory is on a local filesystem and there is ample kernel cache
1059  * space. The performance advantage is greater when the DBA extension is
1060  * available than it is with the PHP port.
1061  *
1062  * See Cdb.php and http://cr.yp.to/cdb.html
1063  */
1064 class LCStore_CDB implements LCStore {
1065         var $readers, $writer, $currentLang, $directory;
1066
1067         function __construct( $conf = array() ) {
1068                 global $wgCacheDirectory;
1069
1070                 if ( isset( $conf['directory'] ) ) {
1071                         $this->directory = $conf['directory'];
1072                 } else {
1073                         $this->directory = $wgCacheDirectory;
1074                 }
1075         }
1076
1077         public function get( $code, $key ) {
1078                 if ( !isset( $this->readers[$code] ) ) {
1079                         $fileName = $this->getFileName( $code );
1080
1081                         if ( !file_exists( $fileName ) ) {
1082                                 $this->readers[$code] = false;
1083                         } else {
1084                                 $this->readers[$code] = CdbReader::open( $fileName );
1085                         }
1086                 }
1087
1088                 if ( !$this->readers[$code] ) {
1089                         return null;
1090                 } else {
1091                         $value = $this->readers[$code]->get( $key );
1092
1093                         if ( $value === false ) {
1094                                 return null;
1095                         }
1096                         return unserialize( $value );
1097                 }
1098         }
1099
1100         public function startWrite( $code ) {
1101                 if ( !file_exists( $this->directory ) ) {
1102                         if ( !wfMkdirParents( $this->directory, null, __METHOD__ ) ) {
1103                                 throw new MWException( "Unable to create the localisation store " .
1104                                         "directory \"{$this->directory}\"" );
1105                         }
1106                 }
1107
1108                 // Close reader to stop permission errors on write
1109                 if ( !empty( $this->readers[$code] ) ) {
1110                         $this->readers[$code]->close();
1111                 }
1112
1113                 $this->writer = CdbWriter::open( $this->getFileName( $code ) );
1114                 $this->currentLang = $code;
1115         }
1116
1117         public function finishWrite() {
1118                 // Close the writer
1119                 $this->writer->close();
1120                 $this->writer = null;
1121                 unset( $this->readers[$this->currentLang] );
1122                 $this->currentLang = null;
1123         }
1124
1125         public function set( $key, $value ) {
1126                 if ( is_null( $this->writer ) ) {
1127                         throw new MWException( __CLASS__ . ': must call startWrite() before calling set()' );
1128                 }
1129                 $this->writer->set( $key, serialize( $value ) );
1130         }
1131
1132         protected function getFileName( $code ) {
1133                 if ( !$code || strpos( $code, '/' ) !== false ) {
1134                         throw new MWException( __METHOD__ . ": Invalid language \"$code\"" );
1135                 }
1136                 return "{$this->directory}/l10n_cache-$code.cdb";
1137         }
1138 }
1139
1140 /**
1141  * Null store backend, used to avoid DB errors during install
1142  */
1143 class LCStore_Null implements LCStore {
1144         public function get( $code, $key ) {
1145                 return null;
1146         }
1147
1148         public function startWrite( $code ) {}
1149         public function finishWrite() {}
1150         public function set( $key, $value ) {}
1151 }
1152
1153 /**
1154  * A localisation cache optimised for loading large amounts of data for many
1155  * languages. Used by rebuildLocalisationCache.php.
1156  */
1157 class LocalisationCache_BulkLoad extends LocalisationCache {
1158         /**
1159          * A cache of the contents of data files.
1160          * Core files are serialized to avoid using ~1GB of RAM during a recache.
1161          */
1162         var $fileCache = array();
1163
1164         /**
1165          * Most recently used languages. Uses the linked-list aspect of PHP hashtables
1166          * to keep the most recently used language codes at the end of the array, and
1167          * the language codes that are ready to be deleted at the beginning.
1168          */
1169         var $mruLangs = array();
1170
1171         /**
1172          * Maximum number of languages that may be loaded into $this->data
1173          */
1174         var $maxLoadedLangs = 10;
1175
1176         /**
1177          * @param $fileName
1178          * @param $fileType
1179          * @return array|mixed
1180          */
1181         protected function readPHPFile( $fileName, $fileType ) {
1182                 $serialize = $fileType === 'core';
1183                 if ( !isset( $this->fileCache[$fileName][$fileType] ) ) {
1184                         $data = parent::readPHPFile( $fileName, $fileType );
1185
1186                         if ( $serialize ) {
1187                                 $encData = serialize( $data );
1188                         } else {
1189                                 $encData = $data;
1190                         }
1191
1192                         $this->fileCache[$fileName][$fileType] = $encData;
1193
1194                         return $data;
1195                 } elseif ( $serialize ) {
1196                         return unserialize( $this->fileCache[$fileName][$fileType] );
1197                 } else {
1198                         return $this->fileCache[$fileName][$fileType];
1199                 }
1200         }
1201
1202         /**
1203          * @param $code
1204          * @param $key
1205          * @return mixed
1206          */
1207         public function getItem( $code, $key ) {
1208                 unset( $this->mruLangs[$code] );
1209                 $this->mruLangs[$code] = true;
1210                 return parent::getItem( $code, $key );
1211         }
1212
1213         /**
1214          * @param $code
1215          * @param $key
1216          * @param $subkey
1217          * @return
1218          */
1219         public function getSubitem( $code, $key, $subkey ) {
1220                 unset( $this->mruLangs[$code] );
1221                 $this->mruLangs[$code] = true;
1222                 return parent::getSubitem( $code, $key, $subkey );
1223         }
1224
1225         /**
1226          * @param $code
1227          */
1228         public function recache( $code ) {
1229                 parent::recache( $code );
1230                 unset( $this->mruLangs[$code] );
1231                 $this->mruLangs[$code] = true;
1232                 $this->trimCache();
1233         }
1234
1235         /**
1236          * @param $code
1237          */
1238         public function unload( $code ) {
1239                 unset( $this->mruLangs[$code] );
1240                 parent::unload( $code );
1241         }
1242
1243         /**
1244          * Unload cached languages until there are less than $this->maxLoadedLangs
1245          */
1246         protected function trimCache() {
1247                 while ( count( $this->data ) > $this->maxLoadedLangs && count( $this->mruLangs ) ) {
1248                         reset( $this->mruLangs );
1249                         $code = key( $this->mruLangs );
1250                         wfDebug( __METHOD__ . ": unloading $code\n" );
1251                         $this->unload( $code );
1252                 }
1253         }
1254
1255 }