includes/LocalisationCache.php

   1 <?php
   2
   3 define( 'MW_LC_VERSION', 2 );
   4
   5 /**
   6  * Class for caching the contents of localisation files, Messages*.php
   7  * and *.i18n.php.
   8  *
   9  * An instance of this class is available using Language::getLocalisationCache().
  10  *
  11  * The values retrieved from here are merged, containing items from extension
  12  * files, core messages files and the language fallback sequence (e.g. zh-cn ->
  13  * zh-hans -> en ). Some common errors are corrected, for example namespace
  14  * names with spaces instead of underscores, but heavyweight processing, such
  15  * as grammatical transformation, is done by the caller.
  16  */
  17 class LocalisationCache {
  18         /** Configuration associative array */
  19         var $conf;
  20
  21         /**
  22          * True if recaching should only be done on an explicit call to recache().
  23          * Setting this reduces the overhead of cache freshness checking, which
  24          * requires doing a stat() for every extension i18n file.
  25          */
  26         var $manualRecache = false;
  27
  28         /**
  29          * True to treat all files as expired until they are regenerated by this object.
  30          */
  31         var $forceRecache = false;
  32
  33         /**
  34          * The cache data. 3-d array, where the first key is the language code,
  35          * the second key is the item key e.g. 'messages', and the third key is
  36          * an item specific subkey index. Some items are not arrays and so for those
  37          * items, there are no subkeys.
  38          */
  39         var $data = array();
  40
  41         /**
  42          * The persistent store object. An instance of LCStore.
  43          *
  44          * @var LCStore
  45          */
  46         var $store;
  47
  48         /**
  49          * A 2-d associative array, code/key, where presence indicates that the item
  50          * is loaded. Value arbitrary.
  51          *
  52          * For split items, if set, this indicates that all of the subitems have been
  53          * loaded.
  54          */
  55         var $loadedItems = array();
  56
  57         /**
  58          * A 3-d associative array, code/key/subkey, where presence indicates that
  59          * the subitem is loaded. Only used for the split items, i.e. messages.
  60          */
  61         var $loadedSubitems = array();
  62
  63         /**
  64          * An array where presence of a key indicates that that language has been
  65          * initialised. Initialisation includes checking for cache expiry and doing
  66          * any necessary updates.
  67          */
  68         var $initialisedLangs = array();
  69
  70         /**
  71          * An array mapping non-existent pseudo-languages to fallback languages. This
  72          * is filled by initShallowFallback() when data is requested from a language
  73          * that lacks a Messages*.php file.
  74          */
  75         var $shallowFallbacks = array();
  76
  77         /**
  78          * An array where the keys are codes that have been recached by this instance.
  79          */
  80         var $recachedLangs = array();
  81
  82         /**
  83          * All item keys
  84          */
  85         static public $allKeys = array(
  86                 'fallback', 'namespaceNames', 'bookstoreList',
  87                 'magicWords', 'messages', 'rtl', 'capitalizeAllNouns', 'digitTransformTable',
  88                 'separatorTransformTable', 'fallback8bitEncoding', 'linkPrefixExtension',
  89                 'linkTrail', 'namespaceAliases',
  90                 'dateFormats', 'datePreferences', 'datePreferenceMigrationMap',
  91                 'defaultDateFormat', 'extraUserToggles', 'specialPageAliases',
  92                 'imageFiles', 'preloadedMessages', 'namespaceGenderAliases',
  93                 'digitGroupingPattern'
  94         );
  95
  96         /**
  97          * Keys for items which consist of associative arrays, which may be merged
  98          * by a fallback sequence.
  99          */
 100         static public $mergeableMapKeys = array( 'messages', 'namespaceNames',
 101                 'dateFormats', 'imageFiles', 'preloadedMessages',
 102         );
 103
 104         /**
 105          * Keys for items which are a numbered array.
 106          */
 107         static public $mergeableListKeys = array( 'extraUserToggles' );
 108
 109         /**
 110          * Keys for items which contain an array of arrays of equivalent aliases
 111          * for each subitem. The aliases may be merged by a fallback sequence.
 112          */
 113         static public $mergeableAliasListKeys = array( 'specialPageAliases' );
 114
 115         /**
 116          * Keys for items which contain an associative array, and may be merged if
 117          * the primary value contains the special array key "inherit". That array
 118          * key is removed after the first merge.
 119          */
 120         static public $optionalMergeKeys = array( 'bookstoreList' );
 121
 122         /**
 123          * Keys for items that are formatted like $magicWords
 124          */
 125         static public $magicWordKeys = array( 'magicWords' );
 126
 127         /**
 128          * Keys for items where the subitems are stored in the backend separately.
 129          */
 130         static public $splitKeys = array( 'messages' );
 131
 132         /**
 133          * Keys which are loaded automatically by initLanguage()
 134          */
 135         static public $preloadedKeys = array( 'dateFormats', 'namespaceNames' );
 136
 137         var $mergeableKeys = array();
 138
 139         /**
 140          * Constructor.
 141          * For constructor parameters, see the documentation in DefaultSettings.php
 142          * for $wgLocalisationCacheConf.
 143          *
 144          * @param $conf Array
 145          */
 146         function __construct( $conf ) {
 147                 global $wgCacheDirectory;
 148
 149                 $this->conf = $conf;
 150                 $storeConf = array();
 151                 if ( !empty( $conf['storeClass'] ) ) {
 152                         $storeClass = $conf['storeClass'];
 153                 } else {
 154                         switch ( $conf['store'] ) {
 155                                 case 'files':
 156                                 case 'file':
 157                                         $storeClass = 'LCStore_CDB';
 158                                         break;
 159                                 case 'db':
 160                                         $storeClass = 'LCStore_DB';
 161                                         break;
 162                                 case 'detect':
 163                                         $storeClass = $wgCacheDirectory ? 'LCStore_CDB' : 'LCStore_DB';
 164                                         break;
 165                                 default:
 166                                         throw new MWException(
 167                                                 'Please set $wgLocalisationCacheConf[\'store\'] to something sensible.' );
 168                         }
 169                 }
 170
 171                 wfDebug( get_class( $this ) . ": using store $storeClass\n" );
 172                 if ( !empty( $conf['storeDirectory'] ) ) {
 173                         $storeConf['directory'] = $conf['storeDirectory'];
 174                 }
 175
 176                 $this->store = new $storeClass( $storeConf );
 177                 foreach ( array( 'manualRecache', 'forceRecache' ) as $var ) {
 178                         if ( isset( $conf[$var] ) ) {
 179                                 $this->$var = $conf[$var];
 180                         }
 181                 }
 182         }
 183
 184         /**
 185          * Returns true if the given key is mergeable, that is, if it is an associative
 186          * array which can be merged through a fallback sequence.
 187          * @param $key
 188          * @return bool
 189          */
 190         public function isMergeableKey( $key ) {
 191                 if ( !isset( $this->mergeableKeys ) ) {
 192                         $this->mergeableKeys = array_flip( array_merge(
 193                                 self::$mergeableMapKeys,
 194                                 self::$mergeableListKeys,
 195                                 self::$mergeableAliasListKeys,
 196                                 self::$optionalMergeKeys,
 197                                 self::$magicWordKeys
 198                         ) );
 199                 }
 200                 return isset( $this->mergeableKeys[$key] );
 201         }
 202
 203         /**
 204          * Get a cache item.
 205          *
 206          * Warning: this may be slow for split items (messages), since it will
 207          * need to fetch all of the subitems from the cache individually.
 208          * @param $code
 209          * @param $key
 210          * @return string
 211          */
 212         public function getItem( $code, $key ) {
 213                 if ( !isset( $this->loadedItems[$code][$key] ) ) {
 214                         wfProfileIn( __METHOD__.'-load' );
 215                         $this->loadItem( $code, $key );
 216                         wfProfileOut( __METHOD__.'-load' );
 217                 }
 218
 219                 if ( $key === 'fallback' && isset( $this->shallowFallbacks[$code] ) ) {
 220                         return $this->shallowFallbacks[$code];
 221                 }
 222
 223                 return $this->data[$code][$key];
 224         }
 225
 226         /**
 227          * Get a subitem, for instance a single message for a given language.
 228          * @param $code
 229          * @param $key
 230          * @param $subkey
 231          * @return null
 232          */
 233         public function getSubitem( $code, $key, $subkey ) {
 234                 if ( !isset( $this->loadedSubitems[$code][$key][$subkey] )
 235                         && !isset( $this->loadedItems[$code][$key] ) )
 236                 {
 237                         wfProfileIn( __METHOD__.'-load' );
 238                         $this->loadSubitem( $code, $key, $subkey );
 239                         wfProfileOut( __METHOD__.'-load' );
 240                 }
 241
 242                 if ( isset( $this->data[$code][$key][$subkey] ) ) {
 243                         return $this->data[$code][$key][$subkey];
 244                 } else {
 245                         return null;
 246                 }
 247         }
 248
 249         /**
 250          * Get the list of subitem keys for a given item.
 251          *
 252          * This is faster than array_keys($lc->getItem(...)) for the items listed in
 253          * self::$splitKeys.
 254          *
 255          * Will return null if the item is not found, or false if the item is not an
 256          * array.
 257          * @param $code
 258          * @param $key
 259          * @return bool|null|string
 260          */
 261         public function getSubitemList( $code, $key ) {
 262                 if ( in_array( $key, self::$splitKeys ) ) {
 263                         return $this->getSubitem( $code, 'list', $key );
 264                 } else {
 265                         $item = $this->getItem( $code, $key );
 266                         if ( is_array( $item ) ) {
 267                                 return array_keys( $item );
 268                         } else {
 269                                 return false;
 270                         }
 271                 }
 272         }
 273
 274         /**
 275          * Load an item into the cache.
 276          * @param $code
 277          * @param $key
 278          */
 279         protected function loadItem( $code, $key ) {
 280                 if ( !isset( $this->initialisedLangs[$code] ) ) {
 281                         $this->initLanguage( $code );
 282                 }
 283
 284                 // Check to see if initLanguage() loaded it for us
 285                 if ( isset( $this->loadedItems[$code][$key] ) ) {
 286                         return;
 287                 }
 288
 289                 if ( isset( $this->shallowFallbacks[$code] ) ) {
 290                         $this->loadItem( $this->shallowFallbacks[$code], $key );
 291                         return;
 292                 }
 293
 294                 if ( in_array( $key, self::$splitKeys ) ) {
 295                         $subkeyList = $this->getSubitem( $code, 'list', $key );
 296                         foreach ( $subkeyList as $subkey ) {
 297                                 if ( isset( $this->data[$code][$key][$subkey] ) ) {
 298                                         continue;
 299                                 }
 300                                 $this->data[$code][$key][$subkey] = $this->getSubitem( $code, $key, $subkey );
 301                         }
 302                 } else {
 303                         $this->data[$code][$key] = $this->store->get( $code, $key );
 304                 }
 305
 306                 $this->loadedItems[$code][$key] = true;
 307         }
 308
 309         /**
 310          * Load a subitem into the cache
 311          * @param $code
 312          * @param $key
 313          * @param $subkey
 314          * @return
 315          */
 316         protected function loadSubitem( $code, $key, $subkey ) {
 317                 if ( !in_array( $key, self::$splitKeys ) ) {
 318                         $this->loadItem( $code, $key );
 319                         return;
 320                 }
 321
 322                 if ( !isset( $this->initialisedLangs[$code] ) ) {
 323                         $this->initLanguage( $code );
 324                 }
 325
 326                 // Check to see if initLanguage() loaded it for us
 327                 if ( isset( $this->loadedItems[$code][$key] )
 328                         || isset( $this->loadedSubitems[$code][$key][$subkey] ) )
 329                 {
 330                         return;
 331                 }
 332
 333                 if ( isset( $this->shallowFallbacks[$code] ) ) {
 334                         $this->loadSubitem( $this->shallowFallbacks[$code], $key, $subkey );
 335                         return;
 336                 }
 337
 338                 $value = $this->store->get( $code, "$key:$subkey" );
 339                 $this->data[$code][$key][$subkey] = $value;
 340                 $this->loadedSubitems[$code][$key][$subkey] = true;
 341         }
 342
 343         /**
 344          * Returns true if the cache identified by $code is missing or expired.
 345          */
 346         public function isExpired( $code ) {
 347                 if ( $this->forceRecache && !isset( $this->recachedLangs[$code] ) ) {
 348                         wfDebug( __METHOD__."($code): forced reload\n" );
 349                         return true;
 350                 }
 351
 352                 $deps = $this->store->get( $code, 'deps' );
 353                 if ( $deps === null ) {
 354                         wfDebug( __METHOD__."($code): cache missing, need to make one\n" );
 355                         return true;
 356                 }
 357
 358                 foreach ( $deps as $dep ) {
 359                         // Because we're unserializing stuff from cache, we
 360                         // could receive objects of classes that don't exist
 361                         // anymore (e.g. uninstalled extensions)
 362                         // When this happens, always expire the cache
 363                         if ( !$dep instanceof CacheDependency || $dep->isExpired() ) {
 364                                 wfDebug( __METHOD__."($code): cache for $code expired due to " .
 365                                         get_class( $dep ) . "\n" );
 366                                 return true;
 367                         }
 368                 }
 369
 370                 return false;
 371         }
 372
 373         /**
 374          * Initialise a language in this object. Rebuild the cache if necessary.
 375          * @param $code
 376          */
 377         protected function initLanguage( $code ) {
 378                 if ( isset( $this->initialisedLangs[$code] ) ) {
 379                         return;
 380                 }
 381
 382                 $this->initialisedLangs[$code] = true;
 383
 384                 # If the code is of the wrong form for a Messages*.php file, do a shallow fallback
 385                 if ( !Language::isValidBuiltInCode( $code ) ) {
 386                         $this->initShallowFallback( $code, 'en' );
 387                         return;
 388                 }
 389
 390                 # Recache the data if necessary
 391                 if ( !$this->manualRecache && $this->isExpired( $code ) ) {
 392                         if ( file_exists( Language::getMessagesFileName( $code ) ) ) {
 393                                 $this->recache( $code );
 394                         } elseif ( $code === 'en' ) {
 395                                 throw new MWException( 'MessagesEn.php is missing.' );
 396                         } else {
 397                                 $this->initShallowFallback( $code, 'en' );
 398                         }
 399                         return;
 400                 }
 401
 402                 # Preload some stuff
 403                 $preload = $this->getItem( $code, 'preload' );
 404                 if ( $preload === null ) {
 405                         if ( $this->manualRecache ) {
 406                                 // No Messages*.php file. Do shallow fallback to en.
 407                                 if ( $code === 'en' ) {
 408                                         throw new MWException( 'No localisation cache found for English. ' .
 409                                                 'Please run maintenance/rebuildLocalisationCache.php.' );
 410                                 }
 411                                 $this->initShallowFallback( $code, 'en' );
 412                                 return;
 413                         } else {
 414                                 throw new MWException( 'Invalid or missing localisation cache.' );
 415                         }
 416                 }
 417                 $this->data[$code] = $preload;
 418                 foreach ( $preload as $key => $item ) {
 419                         if ( in_array( $key, self::$splitKeys ) ) {
 420                                 foreach ( $item as $subkey => $subitem ) {
 421                                         $this->loadedSubitems[$code][$key][$subkey] = true;
 422                                 }
 423                         } else {
 424                                 $this->loadedItems[$code][$key] = true;
 425                         }
 426                 }
 427         }
 428
 429         /**
 430          * Create a fallback from one language to another, without creating a
 431          * complete persistent cache.
 432          * @param $primaryCode
 433          * @param $fallbackCode
 434          */
 435         public function initShallowFallback( $primaryCode, $fallbackCode ) {
 436                 $this->data[$primaryCode] =& $this->data[$fallbackCode];
 437                 $this->loadedItems[$primaryCode] =& $this->loadedItems[$fallbackCode];
 438                 $this->loadedSubitems[$primaryCode] =& $this->loadedSubitems[$fallbackCode];
 439                 $this->shallowFallbacks[$primaryCode] = $fallbackCode;
 440         }
 441
 442         /**
 443          * Read a PHP file containing localisation data.
 444          * @param $_fileName
 445          * @param $_fileType
 446          * @return array
 447          */
 448         protected function readPHPFile( $_fileName, $_fileType ) {
 449                 // Disable APC caching
 450                 $_apcEnabled = ini_set( 'apc.cache_by_default', '0' );
 451                 include( $_fileName );
 452                 ini_set( 'apc.cache_by_default', $_apcEnabled );
 453
 454                 if ( $_fileType == 'core' || $_fileType == 'extension' ) {
 455                         $data = compact( self::$allKeys );
 456                 } elseif ( $_fileType == 'aliases' ) {
 457                         $data = compact( 'aliases' );
 458                 } else {
 459                         throw new MWException( __METHOD__.": Invalid file type: $_fileType" );
 460                 }
 461
 462                 return $data;
 463         }
 464
 465         /**
 466          * Merge two localisation values, a primary and a fallback, overwriting the
 467          * primary value in place.
 468          * @param $key
 469          * @param $value
 470          * @param $fallbackValue
 471          */
 472         protected function mergeItem( $key, &$value, $fallbackValue ) {
 473                 if ( !is_null( $value ) ) {
 474                         if ( !is_null( $fallbackValue ) ) {
 475                                 if ( in_array( $key, self::$mergeableMapKeys ) ) {
 476                                         $value = $value + $fallbackValue;
 477                                 } elseif ( in_array( $key, self::$mergeableListKeys ) ) {
 478                                         $value = array_unique( array_merge( $fallbackValue, $value ) );
 479                                 } elseif ( in_array( $key, self::$mergeableAliasListKeys ) ) {
 480                                         $value = array_merge_recursive( $value, $fallbackValue );
 481                                 } elseif ( in_array( $key, self::$optionalMergeKeys ) ) {
 482                                         if ( !empty( $value['inherit'] ) )  {
 483                                                 $value = array_merge( $fallbackValue, $value );
 484                                         }
 485
 486                                         if ( isset( $value['inherit'] ) ) {
 487                                                 unset( $value['inherit'] );
 488                                         }
 489                                 } elseif ( in_array( $key, self::$magicWordKeys ) ) {
 490                                         $this->mergeMagicWords( $value, $fallbackValue );
 491                                 }
 492                         }
 493                 } else {
 494                         $value = $fallbackValue;
 495                 }
 496         }
 497
 498         /**
 499          * @param $value
 500          * @param $fallbackValue
 501          */
 502         protected function mergeMagicWords( &$value, $fallbackValue ) {
 503                 foreach ( $fallbackValue as $magicName => $fallbackInfo ) {
 504                         if ( !isset( $value[$magicName] ) ) {
 505                                 $value[$magicName] = $fallbackInfo;
 506                         } else {
 507                                 $oldSynonyms = array_slice( $fallbackInfo, 1 );
 508                                 $newSynonyms = array_slice( $value[$magicName], 1 );
 509                                 $synonyms = array_values( array_unique( array_merge(
 510                                         $newSynonyms, $oldSynonyms ) ) );
 511                                 $value[$magicName] = array_merge( array( $fallbackInfo[0] ), $synonyms );
 512                         }
 513                 }
 514         }
 515
 516         /**
 517          * Given an array mapping language code to localisation value, such as is
 518          * found in extension *.i18n.php files, iterate through a fallback sequence
 519          * to merge the given data with an existing primary value.
 520          *
 521          * Returns true if any data from the extension array was used, false
 522          * otherwise.
 523          * @param $codeSequence
 524          * @param $key
 525          * @param $value
 526          * @param $fallbackValue
 527          * @return bool
 528          */
 529         protected function mergeExtensionItem( $codeSequence, $key, &$value, $fallbackValue ) {
 530                 $used = false;
 531                 foreach ( $codeSequence as $code ) {
 532                         if ( isset( $fallbackValue[$code] ) ) {
 533                                 $this->mergeItem( $key, $value, $fallbackValue[$code] );
 534                                 $used = true;
 535                         }
 536                 }
 537
 538                 return $used;
 539         }
 540
 541         /**
 542          * Load localisation data for a given language for both core and extensions
 543          * and save it to the persistent cache store and the process cache
 544          * @param $code
 545          */
 546         public function recache( $code ) {
 547                 global $wgExtensionMessagesFiles, $wgExtensionAliasesFiles;
 548                 wfProfileIn( __METHOD__ );
 549
 550                 if ( !$code ) {
 551                         throw new MWException( "Invalid language code requested" );
 552                 }
 553                 $this->recachedLangs[$code] = true;
 554
 555                 # Initial values
 556                 $initialData = array_combine(
 557                         self::$allKeys,
 558                         array_fill( 0, count( self::$allKeys ), null ) );
 559                 $coreData = $initialData;
 560                 $deps = array();
 561
 562                 # Load the primary localisation from the source file
 563                 $fileName = Language::getMessagesFileName( $code );
 564                 if ( !file_exists( $fileName ) ) {
 565                         wfDebug( __METHOD__.": no localisation file for $code, using fallback to en\n" );
 566                         $coreData['fallback'] = 'en';
 567                 } else {
 568                         $deps[] = new FileDependency( $fileName );
 569                         $data = $this->readPHPFile( $fileName, 'core' );
 570                         wfDebug( __METHOD__.": got localisation for $code from source\n" );
 571
 572                         # Merge primary localisation
 573                         foreach ( $data as $key => $value ) {
 574                                 $this->mergeItem( $key, $coreData[$key], $value );
 575                         }
 576
 577                 }
 578
 579                 # Fill in the fallback if it's not there already
 580                 if ( is_null( $coreData['fallback'] ) ) {
 581                         $coreData['fallback'] = $code === 'en' ? false : 'en';
 582                 }
 583
 584                 if ( $coreData['fallback'] === false ) {
 585                         $coreData['fallbackSequence'] = array();
 586                 } else {
 587                         $coreData['fallbackSequence'] = array_map( 'trim', explode( ',', $coreData['fallback'] ) );
 588                         $len = count( $coreData['fallbackSequence'] );
 589
 590                         # Ensure that the sequence ends at en
 591                         if ( $coreData['fallbackSequence'][$len - 1] !== 'en' ) {
 592                                 $coreData['fallbackSequence'][] = 'en';
 593                         }
 594
 595                         # Load the fallback localisation item by item and merge it
 596                         foreach ( $coreData['fallbackSequence'] as $fbCode ) {
 597                                 # Load the secondary localisation from the source file to
 598                                 # avoid infinite cycles on cyclic fallbacks
 599                                 $fbFilename = Language::getMessagesFileName( $fbCode );
 600
 601                                 if ( !file_exists( $fbFilename ) ) {
 602                                         continue;
 603                                 }
 604
 605                                 $deps[] = new FileDependency( $fbFilename );
 606                                 $fbData = $this->readPHPFile( $fbFilename, 'core' );
 607
 608                                 foreach ( self::$allKeys as $key ) {
 609                                         if ( !isset( $fbData[$key] ) ) {
 610                                                 continue;
 611                                         }
 612
 613                                         if ( is_null( $coreData[$key] ) || $this->isMergeableKey( $key ) ) {
 614                                                 $this->mergeItem( $key, $coreData[$key], $fbData[$key] );
 615                                         }
 616                                 }
 617                         }
 618                 }
 619
 620                 $codeSequence = array_merge( array( $code ), $coreData['fallbackSequence'] );
 621
 622                 # Load the extension localisations
 623                 # This is done after the core because we know the fallback sequence now.
 624                 # But it has a higher precedence for merging so that we can support things
 625                 # like site-specific message overrides.
 626                 $allData = $initialData;
 627                 foreach ( $wgExtensionMessagesFiles as $fileName ) {
 628                         $data = $this->readPHPFile( $fileName, 'extension' );
 629                         $used = false;
 630
 631                         foreach ( $data as $key => $item ) {
 632                                 if( $this->mergeExtensionItem( $codeSequence, $key, $allData[$key], $item ) ) {
 633                                         $used = true;
 634                                 }
 635                         }
 636
 637                         if ( $used ) {
 638                                 $deps[] = new FileDependency( $fileName );
 639                         }
 640                 }
 641
 642                 # Load deprecated $wgExtensionAliasesFiles
 643                 foreach ( $wgExtensionAliasesFiles as $fileName ) {
 644                         $data = $this->readPHPFile( $fileName, 'aliases' );
 645
 646                         if ( !isset( $data['aliases'] ) ) {
 647                                 continue;
 648                         }
 649
 650                         $used = $this->mergeExtensionItem( $codeSequence, 'specialPageAliases',
 651                                 $allData['specialPageAliases'], $data['aliases'] );
 652
 653                         if ( $used ) {
 654                                 $deps[] = new FileDependency( $fileName );
 655                         }
 656                 }
 657
 658                 # Merge core data into extension data
 659                 foreach ( $coreData as $key => $item ) {
 660                         $this->mergeItem( $key, $allData[$key], $item );
 661                 }
 662
 663                 # Add cache dependencies for any referenced globals
 664                 $deps['wgExtensionMessagesFiles'] = new GlobalDependency( 'wgExtensionMessagesFiles' );
 665                 $deps['wgExtensionAliasesFiles'] = new GlobalDependency( 'wgExtensionAliasesFiles' );
 666                 $deps['version'] = new ConstantDependency( 'MW_LC_VERSION' );
 667
 668                 # Add dependencies to the cache entry
 669                 $allData['deps'] = $deps;
 670
 671                 # Replace spaces with underscores in namespace names
 672                 $allData['namespaceNames'] = str_replace( ' ', '_', $allData['namespaceNames'] );
 673
 674                 # And do the same for special page aliases. $page is an array.
 675                 foreach ( $allData['specialPageAliases'] as &$page ) {
 676                         $page = str_replace( ' ', '_', $page );
 677                 }
 678                 # Decouple the reference to prevent accidental damage
 679                 unset($page);
 680
 681                 # Set the list keys
 682                 $allData['list'] = array();
 683                 foreach ( self::$splitKeys as $key ) {
 684                         $allData['list'][$key] = array_keys( $allData[$key] );
 685                 }
 686
 687                 # Run hooks
 688                 wfRunHooks( 'LocalisationCacheRecache', array( $this, $code, &$allData ) );
 689
 690                 if ( is_null( $allData['namespaceNames'] ) ) {
 691                         throw new MWException( __METHOD__.': Localisation data failed sanity check! ' .
 692                                 'Check that your languages/messages/MessagesEn.php file is intact.' );
 693                 }
 694
 695                 # Set the preload key
 696                 $allData['preload'] = $this->buildPreload( $allData );
 697
 698                 # Save to the process cache and register the items loaded
 699                 $this->data[$code] = $allData;
 700                 foreach ( $allData as $key => $item ) {
 701                         $this->loadedItems[$code][$key] = true;
 702                 }
 703
 704                 # Save to the persistent cache
 705                 $this->store->startWrite( $code );
 706                 foreach ( $allData as $key => $value ) {
 707                         if ( in_array( $key, self::$splitKeys ) ) {
 708                                 foreach ( $value as $subkey => $subvalue ) {
 709                                         $this->store->set( "$key:$subkey", $subvalue );
 710                                 }
 711                         } else {
 712                                 $this->store->set( $key, $value );
 713                         }
 714                 }
 715                 $this->store->finishWrite();
 716
 717                 # Clear out the MessageBlobStore
 718                 # HACK: If using a null (i.e. disabled) storage backend, we
 719                 # can't write to the MessageBlobStore either
 720                 if ( !$this->store instanceof LCStore_Null ) {
 721                         MessageBlobStore::clear();
 722                 }
 723
 724                 wfProfileOut( __METHOD__ );
 725         }
 726
 727         /**
 728          * Build the preload item from the given pre-cache data.
 729          *
 730          * The preload item will be loaded automatically, improving performance
 731          * for the commonly-requested items it contains.
 732          * @param $data
 733          * @return array
 734          */
 735         protected function buildPreload( $data ) {
 736                 $preload = array( 'messages' => array() );
 737                 foreach ( self::$preloadedKeys as $key ) {
 738                         $preload[$key] = $data[$key];
 739                 }
 740
 741                 foreach ( $data['preloadedMessages'] as $subkey ) {
 742                         if ( isset( $data['messages'][$subkey] ) ) {
 743                                 $subitem = $data['messages'][$subkey];
 744                         } else {
 745                                 $subitem = null;
 746                         }
 747                         $preload['messages'][$subkey] = $subitem;
 748                 }
 749
 750                 return $preload;
 751         }
 752
 753         /**
 754          * Unload the data for a given language from the object cache.
 755          * Reduces memory usage.
 756          * @param $code
 757          */
 758         public function unload( $code ) {
 759                 unset( $this->data[$code] );
 760                 unset( $this->loadedItems[$code] );
 761                 unset( $this->loadedSubitems[$code] );
 762                 unset( $this->initialisedLangs[$code] );
 763
 764                 foreach ( $this->shallowFallbacks as $shallowCode => $fbCode ) {
 765                         if ( $fbCode === $code ) {
 766                                 $this->unload( $shallowCode );
 767                         }
 768                 }
 769         }
 770
 771         /**
 772          * Unload all data
 773          */
 774         public function unloadAll() {
 775                 foreach ( $this->initialisedLangs as $lang => $unused ) {
 776                         $this->unload( $lang );
 777                 }
 778         }
 779
 780         /**
 781          * Disable the storage backend
 782          */
 783         public function disableBackend() {
 784                 $this->store = new LCStore_Null;
 785                 $this->manualRecache = false;
 786         }
 787 }
 788
 789 /**
 790  * Interface for the persistence layer of LocalisationCache.
 791  *
 792  * The persistence layer is two-level hierarchical cache. The first level
 793  * is the language, the second level is the item or subitem.
 794  *
 795  * Since the data for a whole language is rebuilt in one operation, it needs
 796  * to have a fast and atomic method for deleting or replacing all of the
 797  * current data for a given language. The interface reflects this bulk update
 798  * operation. Callers writing to the cache must first call startWrite(), then
 799  * will call set() a couple of thousand times, then will call finishWrite()
 800  * to commit the operation. When finishWrite() is called, the cache is
 801  * expected to delete all data previously stored for that language.
 802  *
 803  * The values stored are PHP variables suitable for serialize(). Implementations
 804  * of LCStore are responsible for serializing and unserializing.
 805  */
 806 interface LCStore {
 807         /**
 808          * Get a value.
 809          * @param $code Language code
 810          * @param $key Cache key
 811          */
 812         function get( $code, $key );
 813
 814         /**
 815          * Start a write transaction.
 816          * @param $code Language code
 817          */
 818         function startWrite( $code );
 819
 820         /**
 821          * Finish a write transaction.
 822          */
 823         function finishWrite();
 824
 825         /**
 826          * Set a key to a given value. startWrite() must be called before this
 827          * is called, and finishWrite() must be called afterwards.
 828          * @param $key
 829          * @param $value
 830          */
 831         function set( $key, $value );
 832 }
 833
 834 /**
 835  * LCStore implementation which uses the standard DB functions to store data.
 836  * This will work on any MediaWiki installation.
 837  */
 838 class LCStore_DB implements LCStore {
 839         var $currentLang;
 840         var $writesDone = false;
 841
 842         /**
 843          * @var DatabaseBase
 844          */
 845         var $dbw;
 846         var $batch;
 847         var $readOnly = false;
 848
 849         public function get( $code, $key ) {
 850                 if ( $this->writesDone ) {
 851                         $db = wfGetDB( DB_MASTER );
 852                 } else {
 853                         $db = wfGetDB( DB_SLAVE );
 854                 }
 855                 $row = $db->selectRow( 'l10n_cache', array( 'lc_value' ),
 856                         array( 'lc_lang' => $code, 'lc_key' => $key ), __METHOD__ );
 857                 if ( $row ) {
 858                         return unserialize( $row->lc_value );
 859                 } else {
 860                         return null;
 861                 }
 862         }
 863
 864         public function startWrite( $code ) {
 865                 if ( $this->readOnly ) {
 866                         return;
 867                 }
 868
 869                 if ( !$code ) {
 870                         throw new MWException( __METHOD__.": Invalid language \"$code\"" );
 871                 }
 872
 873                 $this->dbw = wfGetDB( DB_MASTER );
 874                 try {
 875                         $this->dbw->begin();
 876                         $this->dbw->delete( 'l10n_cache', array( 'lc_lang' => $code ), __METHOD__ );
 877                 } catch ( DBQueryError $e ) {
 878                         if ( $this->dbw->wasReadOnlyError() ) {
 879                                 $this->readOnly = true;
 880                                 $this->dbw->rollback();
 881                                 $this->dbw->ignoreErrors( false );
 882                                 return;
 883                         } else {
 884                                 throw $e;
 885                         }
 886                 }
 887
 888                 $this->currentLang = $code;
 889                 $this->batch = array();
 890         }
 891
 892         public function finishWrite() {
 893                 if ( $this->readOnly ) {
 894                         return;
 895                 }
 896
 897                 if ( $this->batch ) {
 898                         $this->dbw->insert( 'l10n_cache', $this->batch, __METHOD__ );
 899                 }
 900
 901                 $this->dbw->commit();
 902                 $this->currentLang = null;
 903                 $this->dbw = null;
 904                 $this->batch = array();
 905                 $this->writesDone = true;
 906         }
 907
 908         public function set( $key, $value ) {
 909                 if ( $this->readOnly ) {
 910                         return;
 911                 }
 912
 913                 if ( is_null( $this->currentLang ) ) {
 914                         throw new MWException( __CLASS__.': must call startWrite() before calling set()' );
 915                 }
 916
 917                 $this->batch[] = array(
 918                         'lc_lang' => $this->currentLang,
 919                         'lc_key' => $key,
 920                         'lc_value' => serialize( $value ) );
 921
 922                 if ( count( $this->batch ) >= 100 ) {
 923                         $this->dbw->insert( 'l10n_cache', $this->batch, __METHOD__ );
 924                         $this->batch = array();
 925                 }
 926         }
 927 }
 928
 929 /**
 930  * LCStore implementation which stores data as a collection of CDB files in the
 931  * directory given by $wgCacheDirectory. If $wgCacheDirectory is not set, this
 932  * will throw an exception.
 933  *
 934  * Profiling indicates that on Linux, this implementation outperforms MySQL if
 935  * the directory is on a local filesystem and there is ample kernel cache
 936  * space. The performance advantage is greater when the DBA extension is
 937  * available than it is with the PHP port.
 938  *
 939  * See Cdb.php and http://cr.yp.to/cdb.html
 940  */
 941 class LCStore_CDB implements LCStore {
 942         var $readers, $writer, $currentLang, $directory;
 943
 944         function __construct( $conf = array() ) {
 945                 global $wgCacheDirectory;
 946
 947                 if ( isset( $conf['directory'] ) ) {
 948                         $this->directory = $conf['directory'];
 949                 } else {
 950                         $this->directory = $wgCacheDirectory;
 951                 }
 952         }
 953
 954         public function get( $code, $key ) {
 955                 if ( !isset( $this->readers[$code] ) ) {
 956                         $fileName = $this->getFileName( $code );
 957
 958                         if ( !file_exists( $fileName ) ) {
 959                                 $this->readers[$code] = false;
 960                         } else {
 961                                 $this->readers[$code] = CdbReader::open( $fileName );
 962                         }
 963                 }
 964
 965                 if ( !$this->readers[$code] ) {
 966                         return null;
 967                 } else {
 968                         $value = $this->readers[$code]->get( $key );
 969
 970                         if ( $value === false ) {
 971                                 return null;
 972                         }
 973                         return unserialize( $value );
 974                 }
 975         }
 976
 977         public function startWrite( $code ) {
 978                 if ( !file_exists( $this->directory ) ) {
 979                         if ( !wfMkdirParents( $this->directory, null, __METHOD__ ) ) {
 980                                 throw new MWException( "Unable to create the localisation store " .
 981                                         "directory \"{$this->directory}\"" );
 982                         }
 983                 }
 984
 985                 // Close reader to stop permission errors on write
 986                 if( !empty($this->readers[$code]) ) {
 987                         $this->readers[$code]->close();
 988                 }
 989
 990                 $this->writer = CdbWriter::open( $this->getFileName( $code ) );
 991                 $this->currentLang = $code;
 992         }
 993
 994         public function finishWrite() {
 995                 // Close the writer
 996                 $this->writer->close();
 997                 $this->writer = null;
 998                 unset( $this->readers[$this->currentLang] );
 999                 $this->currentLang = null;
1000         }
1001
1002         public function set( $key, $value ) {
1003                 if ( is_null( $this->writer ) ) {
1004                         throw new MWException( __CLASS__.': must call startWrite() before calling set()' );
1005                 }
1006                 $this->writer->set( $key, serialize( $value ) );
1007         }
1008
1009         protected function getFileName( $code ) {
1010                 if ( !$code || strpos( $code, '/' ) !== false ) {
1011                         throw new MWException( __METHOD__.": Invalid language \"$code\"" );
1012                 }
1013                 return "{$this->directory}/l10n_cache-$code.cdb";
1014         }
1015 }
1016
1017 /**
1018  * Null store backend, used to avoid DB errors during install
1019  */
1020 class LCStore_Null implements LCStore {
1021         public function get( $code, $key ) {
1022                 return null;
1023         }
1024
1025         public function startWrite( $code ) {}
1026         public function finishWrite() {}
1027         public function set( $key, $value ) {}
1028 }
1029
1030 /**
1031  * A localisation cache optimised for loading large amounts of data for many
1032  * languages. Used by rebuildLocalisationCache.php.
1033  */
1034 class LocalisationCache_BulkLoad extends LocalisationCache {
1035         /**
1036          * A cache of the contents of data files.
1037          * Core files are serialized to avoid using ~1GB of RAM during a recache.
1038          */
1039         var $fileCache = array();
1040
1041         /**
1042          * Most recently used languages. Uses the linked-list aspect of PHP hashtables
1043          * to keep the most recently used language codes at the end of the array, and
1044          * the language codes that are ready to be deleted at the beginning.
1045          */
1046         var $mruLangs = array();
1047
1048         /**
1049          * Maximum number of languages that may be loaded into $this->data
1050          */
1051         var $maxLoadedLangs = 10;
1052
1053         /**
1054          * @param $fileName
1055          * @param $fileType
1056          * @return array|mixed
1057          */
1058         protected function readPHPFile( $fileName, $fileType ) {
1059                 $serialize = $fileType === 'core';
1060                 if ( !isset( $this->fileCache[$fileName][$fileType] ) ) {
1061                         $data = parent::readPHPFile( $fileName, $fileType );
1062
1063                         if ( $serialize ) {
1064                                 $encData = serialize( $data );
1065                         } else {
1066                                 $encData = $data;
1067                         }
1068
1069                         $this->fileCache[$fileName][$fileType] = $encData;
1070
1071                         return $data;
1072                 } elseif ( $serialize ) {
1073                         return unserialize( $this->fileCache[$fileName][$fileType] );
1074                 } else {
1075                         return $this->fileCache[$fileName][$fileType];
1076                 }
1077         }
1078
1079         /**
1080          * @param $code
1081          * @param $key
1082          * @return string
1083          */
1084         public function getItem( $code, $key ) {
1085                 unset( $this->mruLangs[$code] );
1086                 $this->mruLangs[$code] = true;
1087                 return parent::getItem( $code, $key );
1088         }
1089
1090         /**
1091          * @param $code
1092          * @param $key
1093          * @param $subkey
1094          * @return
1095          */
1096         public function getSubitem( $code, $key, $subkey ) {
1097                 unset( $this->mruLangs[$code] );
1098                 $this->mruLangs[$code] = true;
1099                 return parent::getSubitem( $code, $key, $subkey );
1100         }
1101
1102         /**
1103          * @param $code
1104          */
1105         public function recache( $code ) {
1106                 parent::recache( $code );
1107                 unset( $this->mruLangs[$code] );
1108                 $this->mruLangs[$code] = true;
1109                 $this->trimCache();
1110         }
1111
1112         /**
1113          * @param $code
1114          */
1115         public function unload( $code ) {
1116                 unset( $this->mruLangs[$code] );
1117                 parent::unload( $code );
1118         }
1119
1120         /**
1121          * Unload cached languages until there are less than $this->maxLoadedLangs
1122          */
1123         protected function trimCache() {
1124                 while ( count( $this->data ) > $this->maxLoadedLangs && count( $this->mruLangs ) ) {
1125                         reset( $this->mruLangs );
1126                         $code = key( $this->mruLangs );
1127                         wfDebug( __METHOD__.": unloading $code\n" );
1128                         $this->unload( $code );
1129                 }
1130         }
1131 }