--- /dev/null
+<?php
+
+define( 'MW_LC_VERSION', 1 );
+
+/**
+ * Class for caching the contents of localisation files, Messages*.php
+ * and *.i18n.php.
+ *
+ * An instance of this class is available using Language::getLocalisationCache().
+ *
+ * The values retrieved from here are merged, containing items from extension
+ * files, core messages files and the language fallback sequence (e.g. zh-cn ->
+ * zh-hans -> en ). Some common errors are corrected, for example namespace
+ * names with spaces instead of underscores, but heavyweight processing, such
+ * as grammatical transformation, is done by the caller.
+ */
+class LocalisationCache {
+ /** Configuration associative array */
+ var $conf;
+
+ /**
+ * True if recaching should only be done on an explicit call to recache().
+ * Setting this reduces the overhead of cache freshness checking, which
+ * requires doing a stat() for every extension i18n file.
+ */
+ var $manualRecache = false;
+
+ /**
+ * True to treat all files as expired until they are regenerated by this object.
+ */
+ var $forceRecache = false;
+
+ /**
+ * The cache data. 3-d array, where the first key is the language code,
+ * the second key is the item key e.g. 'messages', and the third key is
+ * an item specific subkey index. Some items are not arrays and so for those
+ * items, there are no subkeys.
+ */
+ var $data = array();
+
+ /**
+ * The persistent store object. An instance of LCStore.
+ */
+ var $store;
+
+ /**
+ * A 2-d associative array, code/key, where presence indicates that the item
+ * is loaded. Value arbitrary.
+ *
+ * For split items, if set, this indicates that all of the subitems have been
+ * loaded.
+ */
+ var $loadedItems = array();
+
+ /**
+ * A 3-d associative array, code/key/subkey, where presence indicates that
+ * the subitem is loaded. Only used for the split items, i.e. messages.
+ */
+ var $loadedSubitems = array();
+
+ /**
+ * An array where presence of a key indicates that that language has been
+ * initialised. Initialisation includes checking for cache expiry and doing
+ * any necessary updates.
+ */
+ var $initialisedLangs = array();
+
+ /**
+ * An array mapping non-existent pseudo-languages to fallback languages. This
+ * is filled by initShallowFallback() when data is requested from a language
+ * that lacks a Messages*.php file.
+ */
+ var $shallowFallbacks = array();
+
+ /**
+ * An array where the keys are codes that have been recached by this instance.
+ */
+ var $recachedLangs = array();
+
+ /**
+ * Data added by extensions using the deprecated $wgMessageCache->addMessages()
+ * interface.
+ */
+ var $legacyData = array();
+
+ /**
+ * All item keys
+ */
+ static public $allKeys = array(
+ 'fallback', 'namespaceNames', 'mathNames', 'bookstoreList',
+ 'magicWords', 'messages', 'rtl', 'capitalizeAllNouns', 'digitTransformTable',
+ 'separatorTransformTable', 'fallback8bitEncoding', 'linkPrefixExtension',
+ 'defaultUserOptionOverrides', 'linkTrail', 'namespaceAliases',
+ 'dateFormats', 'datePreferences', 'datePreferenceMigrationMap',
+ 'defaultDateFormat', 'extraUserToggles', 'specialPageAliases',
+ 'imageFiles', 'preloadedMessages',
+ );
+
+ /**
+ * Keys for items which consist of associative arrays, which may be merged
+ * by a fallback sequence.
+ */
+ static public $mergeableMapKeys = array( 'messages', 'namespaceNames', 'mathNames',
+ 'dateFormats', 'defaultUserOptionOverrides', 'magicWords', 'imageFiles',
+ 'preloadedMessages',
+ );
+
+ /**
+ * Keys for items which are a numbered array.
+ */
+ static public $mergeableListKeys = array( 'extraUserToggles' );
+
+ /**
+ * Keys for items which contain an array of arrays of equivalent aliases
+ * for each subitem. The aliases may be merged by a fallback sequence.
+ */
+ static public $mergeableAliasListKeys = array( 'specialPageAliases' );
+
+ /**
+ * Keys for items which contain an associative array, and may be merged if
+ * the primary value contains the special array key "inherit". That array
+ * key is removed after the first merge.
+ */
+ static public $optionalMergeKeys = array( 'bookstoreList' );
+
+ /**
+ * Keys for items where the subitems are stored in the backend separately.
+ */
+ static public $splitKeys = array( 'messages' );
+
+ /**
+ * Keys which are loaded automatically by initLanguage()
+ */
+ static public $preloadedKeys = array( 'dateFormats', 'namespaceNames',
+ 'defaultUserOptionOverrides' );
+
+ /**
+ * Constructor.
+ * For constructor parameters, see the documentation in DefaultSettings.php
+ * for $wgLocalisationCacheConf.
+ */
+ function __construct( $conf ) {
+ global $wgCacheDirectory;
+
+ $this->conf = $conf;
+ $storeConf = array();
+ if ( !empty( $conf['storeClass'] ) ) {
+ $storeClass = $conf['storeClass'];
+ } else {
+ switch ( $conf['store'] ) {
+ case 'files':
+ case 'file':
+ $storeClass = 'LCStore_CDB';
+ break;
+ case 'db':
+ $storeClass = 'LCStore_DB';
+ break;
+ case 'detect':
+ $storeClass = $wgCacheDirectory ? 'LCStore_CDB' : 'LCStore_DB';
+ break;
+ default:
+ throw new MWException(
+ 'Please set $wgLocalisationCacheConf[\'store\'] to something sensible.' );
+ }
+ }
+
+ wfDebug( get_class( $this ) . ": using store $storeClass\n" );
+ if ( !empty( $conf['storeDirectory'] ) ) {
+ $storeConf['directory'] = $conf['storeDirectory'];
+ }
+
+ $this->store = new $storeClass( $storeConf );
+ foreach ( array( 'manualRecache', 'forceRecache' ) as $var ) {
+ if ( isset( $conf[$var] ) ) {
+ $this->$var = $conf[$var];
+ }
+ }
+ }
+
+ /**
+ * Returns true if the given key is mergeable, that is, if it is an associative
+ * array which can be merged through a fallback sequence.
+ */
+ public function isMergeableKey( $key ) {
+ if ( !isset( $this->mergeableKeys ) ) {
+ $this->mergeableKeys = array_flip( array_merge(
+ self::$mergeableMapKeys,
+ self::$mergeableListKeys,
+ self::$mergeableAliasListKeys,
+ self::$optionalMergeKeys
+ ) );
+ }
+ return isset( $this->mergeableKeys[$key] );
+ }
+
+ /**
+ * Get a cache item.
+ *
+ * Warning: this may be slow for split items (messages), since it will
+ * need to fetch all of the subitems from the cache individually.
+ */
+ public function getItem( $code, $key ) {
+ if ( !isset( $this->loadedItems[$code][$key] ) ) {
+ wfProfileIn( __METHOD__.'-load' );
+ $this->loadItem( $code, $key );
+ wfProfileOut( __METHOD__.'-load' );
+ }
+ if ( $key === 'fallback' && isset( $this->shallowFallbacks[$code] ) ) {
+ return $this->shallowFallbacks[$code];
+ }
+ return $this->data[$code][$key];
+ }
+
+ /**
+ * Get a subitem, for instance a single message for a given language.
+ */
+ public function getSubitem( $code, $key, $subkey ) {
+ if ( isset( $this->legacyData[$code][$key][$subkey] ) ) {
+ return $this->legacyData[$code][$key][$subkey];
+ }
+ if ( !isset( $this->loadedSubitems[$code][$key][$subkey] )
+ && !isset( $this->loadedItems[$code][$key] ) )
+ {
+ wfProfileIn( __METHOD__.'-load' );
+ $this->loadSubitem( $code, $key, $subkey );
+ wfProfileOut( __METHOD__.'-load' );
+ }
+ if ( isset( $this->data[$code][$key][$subkey] ) ) {
+ return $this->data[$code][$key][$subkey];
+ } else {
+ return null;
+ }
+ }
+
+ /**
+ * Get the list of subitem keys for a given item.
+ *
+ * This is faster than array_keys($lc->getItem(...)) for the items listed in
+ * self::$splitKeys.
+ *
+ * Will return null if the item is not found, or false if the item is not an
+ * array.
+ */
+ public function getSubitemList( $code, $key ) {
+ if ( in_array( $key, self::$splitKeys ) ) {
+ return $this->getSubitem( $code, 'list', $key );
+ } else {
+ $item = $this->getItem( $code, $key );
+ if ( is_array( $item ) ) {
+ return array_keys( $item );
+ } else {
+ return false;
+ }
+ }
+ }
+
+ /**
+ * Load an item into the cache.
+ */
+ protected function loadItem( $code, $key ) {
+ if ( !isset( $this->initialisedLangs[$code] ) ) {
+ $this->initLanguage( $code );
+ }
+ // Check to see if initLanguage() loaded it for us
+ if ( isset( $this->loadedItems[$code][$key] ) ) {
+ return;
+ }
+ if ( isset( $this->shallowFallbacks[$code] ) ) {
+ $this->loadItem( $this->shallowFallbacks[$code], $key );
+ return;
+ }
+ if ( in_array( $key, self::$splitKeys ) ) {
+ $subkeyList = $this->getSubitem( $code, 'list', $key );
+ foreach ( $subkeyList as $subkey ) {
+ if ( isset( $this->data[$code][$key][$subkey] ) ) {
+ continue;
+ }
+ $this->data[$code][$key][$subkey] = $this->getSubitem( $code, $key, $subkey );
+ }
+ } else {
+ $this->data[$code][$key] = $this->store->get( $code, $key );
+ }
+ $this->loadedItems[$code][$key] = true;
+ }
+
+ /**
+ * Load a subitem into the cache
+ */
+ protected function loadSubitem( $code, $key, $subkey ) {
+ if ( !in_array( $key, self::$splitKeys ) ) {
+ $this->loadItem( $code, $key );
+ return;
+ }
+ if ( !isset( $this->initialisedLangs[$code] ) ) {
+ $this->initLanguage( $code );
+ }
+ // Check to see if initLanguage() loaded it for us
+ if ( isset( $this->loadedItems[$code][$key] )
+ || isset( $this->loadedSubitems[$code][$key][$subkey] ) )
+ {
+ return;
+ }
+ if ( isset( $this->shallowFallbacks[$code] ) ) {
+ $this->loadSubitem( $this->shallowFallbacks[$code], $key, $subkey );
+ return;
+ }
+ $value = $this->store->get( $code, "$key:$subkey" );
+ $this->data[$code][$key][$subkey] = $value;
+ $this->loadedSubitems[$code][$key][$subkey] = true;
+ }
+
+ /**
+ * Returns true if the cache identified by $code is missing or expired.
+ */
+ public function isExpired( $code ) {
+ if ( $this->forceRecache && !isset( $this->recachedLangs[$code] ) ) {
+ wfDebug( __METHOD__."($code): forced reload\n" );
+ return true;
+ }
+
+ $deps = $this->store->get( $code, 'deps' );
+ if ( $deps === null ) {
+ wfDebug( __METHOD__."($code): cache missing, need to make one\n" );
+ return true;
+ }
+ foreach ( $deps as $dep ) {
+ // Because we're unserializing stuff from cache, we
+ // could receive objects of classes that don't exist
+ // anymore (e.g. uninstalled extensions)
+ // When this happens, always expire the cache
+ if ( !$dep instanceof CacheDependency || $dep->isExpired() ) {
+ wfDebug( __METHOD__."($code): cache for $code expired due to " .
+ get_class( $dep ) . "\n" );
+ return true;
+ }
+ }
+ return false;
+ }
+
+ /**
+ * Initialise a language in this object. Rebuild the cache if necessary.
+ */
+ protected function initLanguage( $code ) {
+ if ( isset( $this->initialisedLangs[$code] ) ) {
+ return;
+ }
+ $this->initialisedLangs[$code] = true;
+
+ # Recache the data if necessary
+ if ( !$this->manualRecache && $this->isExpired( $code ) ) {
+ if ( file_exists( Language::getMessagesFileName( $code ) ) ) {
+ $this->recache( $code );
+ } elseif ( $code === 'en' ) {
+ throw new MWException( 'MessagesEn.php is missing.' );
+ } else {
+ $this->initShallowFallback( $code, 'en' );
+ }
+ return;
+ }
+
+ # Preload some stuff
+ $preload = $this->getItem( $code, 'preload' );
+ if ( $preload === null ) {
+ if ( $this->manualRecache ) {
+ // No Messages*.php file. Do shallow fallback to en.
+ if ( $code === 'en' ) {
+ throw new MWException( 'No localisation cache found for English. ' .
+ 'Please run maintenance/rebuildLocalisationCache.php.' );
+ }
+ $this->initShallowFallback( $code, 'en' );
+ return;
+ } else {
+ throw new MWException( 'Invalid or missing localisation cache.' );
+ }
+ }
+ $this->data[$code] = $preload;
+ foreach ( $preload as $key => $item ) {
+ if ( in_array( $key, self::$splitKeys ) ) {
+ foreach ( $item as $subkey => $subitem ) {
+ $this->loadedSubitems[$code][$key][$subkey] = true;
+ }
+ } else {
+ $this->loadedItems[$code][$key] = true;
+ }
+ }
+ }
+
+ /**
+ * Create a fallback from one language to another, without creating a
+ * complete persistent cache.
+ */
+ public function initShallowFallback( $primaryCode, $fallbackCode ) {
+ $this->data[$primaryCode] =& $this->data[$fallbackCode];
+ $this->loadedItems[$primaryCode] =& $this->loadedItems[$fallbackCode];
+ $this->loadedSubitems[$primaryCode] =& $this->loadedSubitems[$fallbackCode];
+ $this->shallowFallbacks[$primaryCode] = $fallbackCode;
+ }
+
+ /**
+ * Read a PHP file containing localisation data.
+ */
+ protected function readPHPFile( $_fileName, $_fileType ) {
+ // Disable APC caching
+ $_apcEnabled = ini_set( 'apc.cache_by_default', '0' );
+ include( $_fileName );
+ ini_set( 'apc.cache_by_default', $_apcEnabled );
+
+ if ( $_fileType == 'core' || $_fileType == 'extension' ) {
+ $data = compact( self::$allKeys );
+ } elseif ( $_fileType == 'aliases' ) {
+ $data = compact( 'aliases' );
+ } else {
+ throw new MWException( __METHOD__.": Invalid file type: $_fileType" );
+ }
+ return $data;
+ }
+
+ /**
+ * Merge two localisation values, a primary and a fallback, overwriting the
+ * primary value in place.
+ */
+ protected function mergeItem( $key, &$value, $fallbackValue ) {
+ if ( !is_null( $value ) ) {
+ if ( !is_null( $fallbackValue ) ) {
+ if ( in_array( $key, self::$mergeableMapKeys ) ) {
+ $value = $value + $fallbackValue;
+ } elseif ( in_array( $key, self::$mergeableListKeys ) ) {
+ $value = array_unique( array_merge( $fallbackValue, $value ) );
+ } elseif ( in_array( $key, self::$mergeableAliasListKeys ) ) {
+ $value = array_merge_recursive( $value, $fallbackValue );
+ } elseif ( in_array( $key, self::$optionalMergeKeys ) ) {
+ if ( !empty( $value['inherit'] ) ) {
+ $value = array_merge( $fallbackValue, $value );
+ }
+ if ( isset( $value['inherit'] ) ) {
+ unset( $value['inherit'] );
+ }
+ }
+ }
+ } else {
+ $value = $fallbackValue;
+ }
+ }
+
+ /**
+ * Given an array mapping language code to localisation value, such as is
+ * found in extension *.i18n.php files, iterate through a fallback sequence
+ * to merge the given data with an existing primary value.
+ *
+ * Returns true if any data from the extension array was used, false
+ * otherwise.
+ */
+ protected function mergeExtensionItem( $codeSequence, $key, &$value, $fallbackValue ) {
+ $used = false;
+ foreach ( $codeSequence as $code ) {
+ if ( isset( $fallbackValue[$code] ) ) {
+ $this->mergeItem( $key, $value, $fallbackValue[$code] );
+ $used = true;
+ }
+ }
+ return $used;
+ }
+
+ /**
+ * Load localisation data for a given language for both core and extensions
+ * and save it to the persistent cache store and the process cache
+ */
+ public function recache( $code ) {
+ static $recursionGuard = array();
+ global $wgExtensionMessagesFiles, $wgExtensionAliasesFiles;
+ wfProfileIn( __METHOD__ );
+
+ if ( !$code ) {
+ throw new MWException( "Invalid language code requested" );
+ }
+ $this->recachedLangs[$code] = true;
+
+ # Initial values
+ $initialData = array_combine(
+ self::$allKeys,
+ array_fill( 0, count( self::$allKeys ), null ) );
+ $coreData = $initialData;
+ $deps = array();
+
+ # Load the primary localisation from the source file
+ $fileName = Language::getMessagesFileName( $code );
+ if ( !file_exists( $fileName ) ) {
+ wfDebug( __METHOD__.": no localisation file for $code, using fallback to en\n" );
+ $coreData['fallback'] = 'en';
+ } else {
+ $deps[] = new FileDependency( $fileName );
+ $data = $this->readPHPFile( $fileName, 'core' );
+ wfDebug( __METHOD__.": got localisation for $code from source\n" );
+
+ # Merge primary localisation
+ foreach ( $data as $key => $value ) {
+ $this->mergeItem( $key, $coreData[$key], $value );
+ }
+ }
+
+ # Fill in the fallback if it's not there already
+ if ( is_null( $coreData['fallback'] ) ) {
+ $coreData['fallback'] = $code === 'en' ? false : 'en';
+ }
+
+ if ( $coreData['fallback'] !== false ) {
+ # Guard against circular references
+ if ( isset( $recursionGuard[$code] ) ) {
+ throw new MWException( "Error: Circular fallback reference in language code $code" );
+ }
+ $recursionGuard[$code] = true;
+
+ # Load the fallback localisation item by item and merge it
+ $deps = array_merge( $deps, $this->getItem( $coreData['fallback'], 'deps' ) );
+ foreach ( self::$allKeys as $key ) {
+ if ( is_null( $coreData[$key] ) || $this->isMergeableKey( $key ) ) {
+ $fallbackValue = $this->getItem( $coreData['fallback'], $key );
+ $this->mergeItem( $key, $coreData[$key], $fallbackValue );
+ }
+ }
+ $fallbackSequence = $this->getItem( $coreData['fallback'], 'fallbackSequence' );
+ array_unshift( $fallbackSequence, $coreData['fallback'] );
+ $coreData['fallbackSequence'] = $fallbackSequence;
+ unset( $recursionGuard[$code] );
+ } else {
+ $coreData['fallbackSequence'] = array();
+ }
+ $codeSequence = array_merge( array( $code ), $coreData['fallbackSequence'] );
+
+ # Load the extension localisations
+ # This is done after the core because we know the fallback sequence now.
+ # But it has a higher precedence for merging so that we can support things
+ # like site-specific message overrides.
+ $allData = $initialData;
+ foreach ( $wgExtensionMessagesFiles as $fileName ) {
+ $data = $this->readPHPFile( $fileName, 'extension' );
+ $used = false;
+ foreach ( $data as $key => $item ) {
+ if( $this->mergeExtensionItem( $codeSequence, $key, $allData[$key], $item ) ) {
+ $used = true;
+ }
+ }
+ if ( $used ) {
+ $deps[] = new FileDependency( $fileName );
+ }
+ }
+
+ # Load deprecated $wgExtensionAliasesFiles
+ foreach ( $wgExtensionAliasesFiles as $fileName ) {
+ $data = $this->readPHPFile( $fileName, 'aliases' );
+ if ( !isset( $data['aliases'] ) ) {
+ continue;
+ }
+ $used = $this->mergeExtensionItem( $codeSequence, 'specialPageAliases',
+ $allData['specialPageAliases'], $data['aliases'] );
+ if ( $used ) {
+ $deps[] = new FileDependency( $fileName );
+ }
+ }
+
+ # Merge core data into extension data
+ foreach ( $coreData as $key => $item ) {
+ $this->mergeItem( $key, $allData[$key], $item );
+ }
+
+ # Add cache dependencies for any referenced globals
+ $deps['wgExtensionMessagesFiles'] = new GlobalDependency( 'wgExtensionMessagesFiles' );
+ $deps['wgExtensionAliasesFiles'] = new GlobalDependency( 'wgExtensionAliasesFiles' );
+ $deps['version'] = new ConstantDependency( 'MW_LC_VERSION' );
+
+ # Add dependencies to the cache entry
+ $allData['deps'] = $deps;
+
+ # Replace spaces with underscores in namespace names
+ $allData['namespaceNames'] = str_replace( ' ', '_', $allData['namespaceNames'] );
+
+ # And do the same for special page aliases. $page is an array.
+ foreach ( $allData['specialPageAliases'] as &$page ) {
+ $page = str_replace( ' ', '_', $page );
+ }
+ # Decouple the reference to prevent accidental damage
+ unset($page);
+
+ # Fix broken defaultUserOptionOverrides
+ if ( !is_array( $allData['defaultUserOptionOverrides'] ) ) {
+ $allData['defaultUserOptionOverrides'] = array();
+ }
+
+ # Set the list keys
+ $allData['list'] = array();
+ foreach ( self::$splitKeys as $key ) {
+ $allData['list'][$key] = array_keys( $allData[$key] );
+ }
+
+ # Run hooks
+ wfRunHooks( 'LocalisationCacheRecache', array( $this, $code, &$allData ) );
+
+ if ( is_null( $allData['defaultUserOptionOverrides'] ) ) {
+ throw new MWException( __METHOD__.': Localisation data failed sanity check! ' .
+ 'Check that your languages/messages/MessagesEn.php file is intact.' );
+ }
+
+ # Set the preload key
+ $allData['preload'] = $this->buildPreload( $allData );
+
+ # Save to the process cache and register the items loaded
+ $this->data[$code] = $allData;
+ foreach ( $allData as $key => $item ) {
+ $this->loadedItems[$code][$key] = true;
+ }
+
+ # Save to the persistent cache
+ $this->store->startWrite( $code );
+ foreach ( $allData as $key => $value ) {
+ if ( in_array( $key, self::$splitKeys ) ) {
+ foreach ( $value as $subkey => $subvalue ) {
+ $this->store->set( "$key:$subkey", $subvalue );
+ }
+ } else {
+ $this->store->set( $key, $value );
+ }
+ }
+ $this->store->finishWrite();
+
+ wfProfileOut( __METHOD__ );
+ }
+
+ /**
+ * Build the preload item from the given pre-cache data.
+ *
+ * The preload item will be loaded automatically, improving performance
+ * for the commonly-requested items it contains.
+ */
+ protected function buildPreload( $data ) {
+ $preload = array( 'messages' => array() );
+ foreach ( self::$preloadedKeys as $key ) {
+ $preload[$key] = $data[$key];
+ }
+ foreach ( $data['preloadedMessages'] as $subkey ) {
+ if ( isset( $data['messages'][$subkey] ) ) {
+ $subitem = $data['messages'][$subkey];
+ } else {
+ $subitem = null;
+ }
+ $preload['messages'][$subkey] = $subitem;
+ }
+ return $preload;
+ }
+
+ /**
+ * Unload the data for a given language from the object cache.
+ * Reduces memory usage.
+ */
+ public function unload( $code ) {
+ unset( $this->data[$code] );
+ unset( $this->loadedItems[$code] );
+ unset( $this->loadedSubitems[$code] );
+ unset( $this->initialisedLangs[$code] );
+ // We don't unload legacyData because there's no way to get it back
+ // again, it's not really a cache
+ foreach ( $this->shallowFallbacks as $shallowCode => $fbCode ) {
+ if ( $fbCode === $code ) {
+ $this->unload( $shallowCode );
+ }
+ }
+ }
+
+ /**
+ * Unload all data
+ */
+ public function unloadAll() {
+ foreach ( $this->initialisedLangs as $lang => $unused ) {
+ $this->unload( $lang );
+ }
+ }
+
+ /**
+ * Add messages to the cache, from an extension that has not yet been
+ * migrated to $wgExtensionMessages or the LocalisationCacheRecache hook.
+ * Called by deprecated function $wgMessageCache->addMessages().
+ */
+ public function addLegacyMessages( $messages ) {
+ foreach ( $messages as $lang => $langMessages ) {
+ if ( isset( $this->legacyData[$lang]['messages'] ) ) {
+ $this->legacyData[$lang]['messages'] =
+ $langMessages + $this->legacyData[$lang]['messages'];
+ } else {
+ $this->legacyData[$lang]['messages'] = $langMessages;
+ }
+ }
+ }
+
+ /**
+ * Disable the storage backend
+ */
+ public function disableBackend() {
+ $this->store = new LCStore_Null;
+ $this->manualRecache = false;
+ }
+}
+
+/**
+ * Interface for the persistence layer of LocalisationCache.
+ *
+ * The persistence layer is two-level hierarchical cache. The first level
+ * is the language, the second level is the item or subitem.
+ *
+ * Since the data for a whole language is rebuilt in one operation, it needs
+ * to have a fast and atomic method for deleting or replacing all of the
+ * current data for a given language. The interface reflects this bulk update
+ * operation. Callers writing to the cache must first call startWrite(), then
+ * will call set() a couple of thousand times, then will call finishWrite()
+ * to commit the operation. When finishWrite() is called, the cache is
+ * expected to delete all data previously stored for that language.
+ *
+ * The values stored are PHP variables suitable for serialize(). Implementations
+ * of LCStore are responsible for serializing and unserializing.
+ */
+interface LCStore {
+ /**
+ * Get a value.
+ * @param $code Language code
+ * @param $key Cache key
+ */
+ public function get( $code, $key );
+
+ /**
+ * Start a write transaction.
+ * @param $code Language code
+ */
+ public function startWrite( $code );
+
+ /**
+ * Finish a write transaction.
+ */
+ public function finishWrite();
+
+ /**
+ * Set a key to a given value. startWrite() must be called before this
+ * is called, and finishWrite() must be called afterwards.
+ */
+ public function set( $key, $value );
+
+}
+
+/**
+ * LCStore implementation which uses the standard DB functions to store data.
+ * This will work on any MediaWiki installation.
+ */
+class LCStore_DB implements LCStore {
+ var $currentLang;
+ var $writesDone = false;
+ var $dbw, $batch;
+ var $readOnly = false;
+
+ public function get( $code, $key ) {
+ if ( $this->writesDone ) {
+ $db = wfGetDB( DB_MASTER );
+ } else {
+ $db = wfGetDB( DB_SLAVE );
+ }
+ $row = $db->selectRow( 'l10n_cache', array( 'lc_value' ),
+ array( 'lc_lang' => $code, 'lc_key' => $key ), __METHOD__ );
+ if ( $row ) {
+ return unserialize( $row->lc_value );
+ } else {
+ return null;
+ }
+ }
+
+ public function startWrite( $code ) {
+ if ( $this->readOnly ) {
+ return;
+ }
+ if ( !$code ) {
+ throw new MWException( __METHOD__.": Invalid language \"$code\"" );
+ }
+ $this->dbw = wfGetDB( DB_MASTER );
+ try {
+ $this->dbw->begin();
+ $this->dbw->delete( 'l10n_cache', array( 'lc_lang' => $code ), __METHOD__ );
+ } catch ( DBQueryError $e ) {
+ if ( $this->dbw->wasReadOnlyError() ) {
+ $this->readOnly = true;
+ $this->dbw->rollback();
+ $this->dbw->ignoreErrors( false );
+ return;
+ } else {
+ throw $e;
+ }
+ }
+ $this->currentLang = $code;
+ $this->batch = array();
+ }
+
+ public function finishWrite() {
+ if ( $this->readOnly ) {
+ return;
+ }
+ if ( $this->batch ) {
+ $this->dbw->insert( 'l10n_cache', $this->batch, __METHOD__ );
+ }
+ $this->dbw->commit();
+ $this->currentLang = null;
+ $this->dbw = null;
+ $this->batch = array();
+ $this->writesDone = true;
+ }
+
+ public function set( $key, $value ) {
+ if ( $this->readOnly ) {
+ return;
+ }
+ if ( is_null( $this->currentLang ) ) {
+ throw new MWException( __CLASS__.': must call startWrite() before calling set()' );
+ }
+ $this->batch[] = array(
+ 'lc_lang' => $this->currentLang,
+ 'lc_key' => $key,
+ 'lc_value' => serialize( $value ) );
+ if ( count( $this->batch ) >= 100 ) {
+ $this->dbw->insert( 'l10n_cache', $this->batch, __METHOD__ );
+ $this->batch = array();
+ }
+ }
+}
+
+/**
+ * LCStore implementation which stores data as a collection of CDB files in the
+ * directory given by $wgCacheDirectory. If $wgCacheDirectory is not set, this
+ * will throw an exception.
+ *
+ * Profiling indicates that on Linux, this implementation outperforms MySQL if
+ * the directory is on a local filesystem and there is ample kernel cache
+ * space. The performance advantage is greater when the DBA extension is
+ * available than it is with the PHP port.
+ *
+ * See Cdb.php and http://cr.yp.to/cdb.html
+ */
+class LCStore_CDB implements LCStore {
+ var $readers, $writer, $currentLang, $directory;
+
+ function __construct( $conf = array() ) {
+ global $wgCacheDirectory;
+ if ( isset( $conf['directory'] ) ) {
+ $this->directory = $conf['directory'];
+ } else {
+ $this->directory = $wgCacheDirectory;
+ }
+ }
+
+ public function get( $code, $key ) {
+ if ( !isset( $this->readers[$code] ) ) {
+ $fileName = $this->getFileName( $code );
+ if ( !file_exists( $fileName ) ) {
+ $this->readers[$code] = false;
+ } else {
+ $this->readers[$code] = CdbReader::open( $fileName );
+ }
+ }
+ if ( !$this->readers[$code] ) {
+ return null;
+ } else {
+ $value = $this->readers[$code]->get( $key );
+ if ( $value === false ) {
+ return null;
+ }
+ return unserialize( $value );
+ }
+ }
+
+ public function startWrite( $code ) {
+ if ( !file_exists( $this->directory ) ) {
+ if ( !wfMkdirParents( $this->directory ) ) {
+ throw new MWException( "Unable to create the localisation store " .
+ "directory \"{$this->directory}\"" );
+ }
+ }
+ // Close reader to stop permission errors on write
+ if( !empty($this->readers[$code]) ) {
+ $this->readers[$code]->close();
+ }
+ $this->writer = CdbWriter::open( $this->getFileName( $code ) );
+ $this->currentLang = $code;
+ }
+
+ public function finishWrite() {
+ // Close the writer
+ $this->writer->close();
+ $this->writer = null;
+ unset( $this->readers[$this->currentLang] );
+ $this->currentLang = null;
+ }
+
+ public function set( $key, $value ) {
+ if ( is_null( $this->writer ) ) {
+ throw new MWException( __CLASS__.': must call startWrite() before calling set()' );
+ }
+ $this->writer->set( $key, serialize( $value ) );
+ }
+
+ protected function getFileName( $code ) {
+ if ( !$code || strpos( $code, '/' ) !== false ) {
+ throw new MWException( __METHOD__.": Invalid language \"$code\"" );
+ }
+ return "{$this->directory}/l10n_cache-$code.cdb";
+ }
+}
+
+/**
+ * Null store backend, used to avoid DB errors during install
+ */
+class LCStore_Null implements LCStore {
+ public function get( $code, $key ) {
+ return null;
+ }
+
+ public function startWrite( $code ) {}
+ public function finishWrite() {}
+ public function set( $key, $value ) {}
+}
+
+/**
+ * A localisation cache optimised for loading large amounts of data for many
+ * languages. Used by rebuildLocalisationCache.php.
+ */
+class LocalisationCache_BulkLoad extends LocalisationCache {
+ /**
+ * A cache of the contents of data files.
+ * Core files are serialized to avoid using ~1GB of RAM during a recache.
+ */
+ var $fileCache = array();
+
+ /**
+ * Most recently used languages. Uses the linked-list aspect of PHP hashtables
+ * to keep the most recently used language codes at the end of the array, and
+ * the language codes that are ready to be deleted at the beginning.
+ */
+ var $mruLangs = array();
+
+ /**
+ * Maximum number of languages that may be loaded into $this->data
+ */
+ var $maxLoadedLangs = 10;
+
+ protected function readPHPFile( $fileName, $fileType ) {
+ $serialize = $fileType === 'core';
+ if ( !isset( $this->fileCache[$fileName][$fileType] ) ) {
+ $data = parent::readPHPFile( $fileName, $fileType );
+ if ( $serialize ) {
+ $encData = serialize( $data );
+ } else {
+ $encData = $data;
+ }
+ $this->fileCache[$fileName][$fileType] = $encData;
+ return $data;
+ } elseif ( $serialize ) {
+ return unserialize( $this->fileCache[$fileName][$fileType] );
+ } else {
+ return $this->fileCache[$fileName][$fileType];
+ }
+ }
+
+ public function getItem( $code, $key ) {
+ unset( $this->mruLangs[$code] );
+ $this->mruLangs[$code] = true;
+ return parent::getItem( $code, $key );
+ }
+
+ public function getSubitem( $code, $key, $subkey ) {
+ unset( $this->mruLangs[$code] );
+ $this->mruLangs[$code] = true;
+ return parent::getSubitem( $code, $key, $subkey );
+ }
+
+ public function recache( $code ) {
+ parent::recache( $code );
+ unset( $this->mruLangs[$code] );
+ $this->mruLangs[$code] = true;
+ $this->trimCache();
+ }
+
+ public function unload( $code ) {
+ unset( $this->mruLangs[$code] );
+ parent::unload( $code );
+ }
+
+ /**
+ * Unload cached languages until there are less than $this->maxLoadedLangs
+ */
+ protected function trimCache() {
+ while ( count( $this->data ) > $this->maxLoadedLangs && count( $this->mruLangs ) ) {
+ reset( $this->mruLangs );
+ $code = key( $this->mruLangs );
+ wfDebug( __METHOD__.": unloading $code\n" );
+ $this->unload( $code );
+ }
+ }
+}
scripts.mit.edu / autoinstallsdev / mediawiki.git / blobdiff