includes/LocalisationCache.php

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