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