Merge "Ignore now empty message for translation"

[mediawiki.git] / includes / filerepo / file / LocalFile.php

<?php
/**
 * Local file in the wiki's own database.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup FileAbstraction
 */

/**
 * Bump this number when serialized cache records may be incompatible.
 */
define( 'MW_FILE_VERSION', 9 );

/**
 * Class to represent a local file in the wiki's own database
 *
 * Provides methods to retrieve paths (physical, logical, URL),
 * to generate image thumbnails or for uploading.
 *
 * Note that only the repo object knows what its file class is called. You should
 * never name a file class explictly outside of the repo class. Instead use the
 * repo's factory functions to generate file objects, for example:
 *
 * RepoGroup::singleton()->getLocalRepo()->newFile( $title );
 *
 * The convenience functions wfLocalFile() and wfFindFile() should be sufficient
 * in most cases.
 *
 * @ingroup FileAbstraction
 */
class LocalFile extends File {
        const CACHE_FIELD_MAX_LEN = 1000;

        /**#@+
         * @private
         */
        var
                $fileExists,       # does the file exist on disk? (loadFromXxx)
                $historyLine,      # Number of line to return by nextHistoryLine() (constructor)
                $historyRes,       # result of the query for the file's history (nextHistoryLine)
                $width,            # \
                $height,           #  |
                $bits,             #   --- returned by getimagesize (loadFromXxx)
                $attr,             # /
                $media_type,       # MEDIATYPE_xxx (bitmap, drawing, audio...)
                $mime,             # MIME type, determined by MimeMagic::guessMimeType
                $major_mime,       # Major mime type
                $minor_mime,       # Minor mime type
                $size,             # Size in bytes (loadFromXxx)
                $metadata,         # Handler-specific metadata
                $timestamp,        # Upload timestamp
                $sha1,             # SHA-1 base 36 content hash
                $user, $user_text, # User, who uploaded the file
                $description,      # Description of current revision of the file
                $dataLoaded,       # Whether or not core data has been loaded from the database (loadFromXxx)
                $extraDataLoaded,  # Whether or not lazy-loaded data has been loaded from the database
                $upgraded,         # Whether the row was upgraded on load
                $locked,           # True if the image row is locked
                $lockedOwnTrx,     # True if the image row is locked with a lock initiated transaction
                $missing,          # True if file is not present in file system. Not to be cached in memcached
                $deleted;          # Bitfield akin to rev_deleted

        /**#@-*/

        /**
         * @var LocalRepo
         */
        var $repo;

        protected $repoClass = 'LocalRepo';

        const LOAD_ALL = 1; // integer; load all the lazy fields too (like metadata)

        /**
         * Create a LocalFile from a title
         * Do not call this except from inside a repo class.
         *
         * Note: $unused param is only here to avoid an E_STRICT
         *
         * @param $title
         * @param $repo
         * @param $unused
         *
         * @return LocalFile
         */
        static function newFromTitle( $title, $repo, $unused = null ) {
                return new self( $title, $repo );
        }

        /**
         * Create a LocalFile from a title
         * Do not call this except from inside a repo class.
         *
         * @param $row
         * @param $repo
         *
         * @return LocalFile
         */
        static function newFromRow( $row, $repo ) {
                $title = Title::makeTitle( NS_FILE, $row->img_name );
                $file = new self( $title, $repo );
                $file->loadFromRow( $row );

                return $file;
        }

        /**
         * Create a LocalFile from a SHA-1 key
         * Do not call this except from inside a repo class.
         *
         * @param string $sha1 base-36 SHA-1
         * @param $repo LocalRepo
         * @param string|bool $timestamp MW_timestamp (optional)
         *
         * @return bool|LocalFile
         */
        static function newFromKey( $sha1, $repo, $timestamp = false ) {
                $dbr = $repo->getSlaveDB();

                $conds = array( 'img_sha1' => $sha1 );
                if ( $timestamp ) {
                        $conds['img_timestamp'] = $dbr->timestamp( $timestamp );
                }

                $row = $dbr->selectRow( 'image', self::selectFields(), $conds, __METHOD__ );
                if ( $row ) {
                        return self::newFromRow( $row, $repo );
                } else {
                        return false;
                }
        }

        /**
         * Fields in the image table
         * @return array
         */
        static function selectFields() {
                return array(
                        'img_name',
                        'img_size',
                        'img_width',
                        'img_height',
                        'img_metadata',
                        'img_bits',
                        'img_media_type',
                        'img_major_mime',
                        'img_minor_mime',
                        'img_description',
                        'img_user',
                        'img_user_text',
                        'img_timestamp',
                        'img_sha1',
                );
        }

        /**
         * Constructor.
         * Do not call this except from inside a repo class.
         */
        function __construct( $title, $repo ) {
                parent::__construct( $title, $repo );

                $this->metadata = '';
                $this->historyLine = 0;
                $this->historyRes = null;
                $this->dataLoaded = false;
                $this->extraDataLoaded = false;

                $this->assertRepoDefined();
                $this->assertTitleDefined();
        }

        /**
         * Get the memcached key for the main data for this file, or false if
         * there is no access to the shared cache.
         * @return bool
         */
        function getCacheKey() {
                $hashedName = md5( $this->getName() );

                return $this->repo->getSharedCacheKey( 'file', $hashedName );
        }

        /**
         * Try to load file metadata from memcached. Returns true on success.
         * @return bool
         */
        function loadFromCache() {
                global $wgMemc;

                wfProfileIn( __METHOD__ );
                $this->dataLoaded = false;
                $this->extraDataLoaded = false;
                $key = $this->getCacheKey();

                if ( !$key ) {
                        wfProfileOut( __METHOD__ );
                        return false;
                }

                $cachedValues = $wgMemc->get( $key );

                // Check if the key existed and belongs to this version of MediaWiki
                if ( isset( $cachedValues['version'] ) && $cachedValues['version'] == MW_FILE_VERSION ) {
                        wfDebug( "Pulling file metadata from cache key $key\n" );
                        $this->fileExists = $cachedValues['fileExists'];
                        if ( $this->fileExists ) {
                                $this->setProps( $cachedValues );
                        }
                        $this->dataLoaded = true;
                        $this->extraDataLoaded = true;
                        foreach ( $this->getLazyCacheFields( '' ) as $field ) {
                                $this->extraDataLoaded = $this->extraDataLoaded && isset( $cachedValues[$field] );
                        }
                }

                if ( $this->dataLoaded ) {
                        wfIncrStats( 'image_cache_hit' );
                } else {
                        wfIncrStats( 'image_cache_miss' );
                }

                wfProfileOut( __METHOD__ );
                return $this->dataLoaded;
        }

        /**
         * Save the file metadata to memcached
         */
        function saveToCache() {
                global $wgMemc;

                $this->load();
                $key = $this->getCacheKey();

                if ( !$key ) {
                        return;
                }

                $fields = $this->getCacheFields( '' );
                $cache = array( 'version' => MW_FILE_VERSION );
                $cache['fileExists'] = $this->fileExists;

                if ( $this->fileExists ) {
                        foreach ( $fields as $field ) {
                                $cache[$field] = $this->$field;
                        }
                }

                // Strip off excessive entries from the subset of fields that can become large.
                // If the cache value gets to large it will not fit in memcached and nothing will
                // get cached at all, causing master queries for any file access.
                foreach ( $this->getLazyCacheFields( '' ) as $field ) {
                        if ( isset( $cache[$field] ) && strlen( $cache[$field] ) > 100 * 1024 ) {
                                unset( $cache[$field] ); // don't let the value get too big
                        }
                }

                // Cache presence for 1 week and negatives for 1 day
                $wgMemc->set( $key, $cache, $this->fileExists ? 86400 * 7 : 86400 );
        }

        /**
         * Load metadata from the file itself
         */
        function loadFromFile() {
                $props = $this->repo->getFileProps( $this->getVirtualUrl() );
                $this->setProps( $props );
        }

        /**
         * @param $prefix string
         * @return array
         */
        function getCacheFields( $prefix = 'img_' ) {
                static $fields = array( 'size', 'width', 'height', 'bits', 'media_type',
                        'major_mime', 'minor_mime', 'metadata', 'timestamp', 'sha1', 'user', 'user_text', 'description' );
                static $results = array();

                if ( $prefix == '' ) {
                        return $fields;
                }

                if ( !isset( $results[$prefix] ) ) {
                        $prefixedFields = array();
                        foreach ( $fields as $field ) {
                                $prefixedFields[] = $prefix . $field;
                        }
                        $results[$prefix] = $prefixedFields;
                }

                return $results[$prefix];
        }

        /**
         * @return array
         */
        function getLazyCacheFields( $prefix = 'img_' ) {
                static $fields = array( 'metadata' );
                static $results = array();

                if ( $prefix == '' ) {
                        return $fields;
                }

                if ( !isset( $results[$prefix] ) ) {
                        $prefixedFields = array();
                        foreach ( $fields as $field ) {
                                $prefixedFields[] = $prefix . $field;
                        }
                        $results[$prefix] = $prefixedFields;
                }

                return $results[$prefix];
        }

        /**
         * Load file metadata from the DB
         */
        function loadFromDB() {
                # Polymorphic function name to distinguish foreign and local fetches
                $fname = get_class( $this ) . '::' . __FUNCTION__;
                wfProfileIn( $fname );

                # Unconditionally set loaded=true, we don't want the accessors constantly rechecking
                $this->dataLoaded = true;
                $this->extraDataLoaded = true;

                $dbr = $this->repo->getMasterDB();
                $row = $dbr->selectRow( 'image', $this->getCacheFields( 'img_' ),
                        array( 'img_name' => $this->getName() ), $fname );

                if ( $row ) {
                        $this->loadFromRow( $row );
                } else {
                        $this->fileExists = false;
                }

                wfProfileOut( $fname );
        }

        /**
         * Load lazy file metadata from the DB.
         * This covers fields that are sometimes not cached.
         */
        protected function loadExtraFromDB() {
                # Polymorphic function name to distinguish foreign and local fetches
                $fname = get_class( $this ) . '::' . __FUNCTION__;
                wfProfileIn( $fname );

                # Unconditionally set loaded=true, we don't want the accessors constantly rechecking
                $this->extraDataLoaded = true;

                $dbr = $this->repo->getSlaveDB();
                // In theory the file could have just been renamed/deleted...oh well
                $row = $dbr->selectRow( 'image', $this->getLazyCacheFields( 'img_' ),
                        array( 'img_name' => $this->getName() ), $fname );

                if ( !$row ) { // fallback to master
                        $dbr = $this->repo->getMasterDB();
                        $row = $dbr->selectRow( 'image', $this->getLazyCacheFields( 'img_' ),
                                array( 'img_name' => $this->getName() ), $fname );
                }

                if ( $row ) {
                        foreach ( $this->unprefixRow( $row, 'img_' ) as $name => $value ) {
                                $this->$name = $value;
                        }
                } else {
                        wfProfileOut( $fname );
                        throw new MWException( "Could not find data for image '{$this->getName()}'." );
                }

                wfProfileOut( $fname );
        }

        /**
         * @param Row $row
         * @param $prefix string
         * @return Array
         */
        protected function unprefixRow( $row, $prefix = 'img_' ) {
                $array = (array)$row;
                $prefixLength = strlen( $prefix );

                // Sanity check prefix once
                if ( substr( key( $array ), 0, $prefixLength ) !== $prefix ) {
                        throw new MWException( __METHOD__ . ': incorrect $prefix parameter' );
                }

                $decoded = array();
                foreach ( $array as $name => $value ) {
                        $decoded[substr( $name, $prefixLength )] = $value;
                }
                return $decoded;
        }

        /**
         * Decode a row from the database (either object or array) to an array
         * with timestamps and MIME types decoded, and the field prefix removed.
         * @param $row
         * @param $prefix string
         * @throws MWException
         * @return array
         */
        function decodeRow( $row, $prefix = 'img_' ) {
                $decoded = $this->unprefixRow( $row, $prefix );

                $decoded['timestamp'] = wfTimestamp( TS_MW, $decoded['timestamp'] );

                if ( empty( $decoded['major_mime'] ) ) {
                        $decoded['mime'] = 'unknown/unknown';
                } else {
                        if ( !$decoded['minor_mime'] ) {
                                $decoded['minor_mime'] = 'unknown';
                        }
                        $decoded['mime'] = $decoded['major_mime'] . '/' . $decoded['minor_mime'];
                }

                # Trim zero padding from char/binary field
                $decoded['sha1'] = rtrim( $decoded['sha1'], "\0" );

                return $decoded;
        }

        /**
         * Load file metadata from a DB result row
         */
        function loadFromRow( $row, $prefix = 'img_' ) {
                $this->dataLoaded = true;
                $this->extraDataLoaded = true;

                $array = $this->decodeRow( $row, $prefix );

                foreach ( $array as $name => $value ) {
                        $this->$name = $value;
                }

                $this->fileExists = true;
                $this->maybeUpgradeRow();
        }

        /**
         * Load file metadata from cache or DB, unless already loaded
         * @param integer $flags
         */
        function load( $flags = 0 ) {
                if ( !$this->dataLoaded ) {
                        if ( !$this->loadFromCache() ) {
                                $this->loadFromDB();
                                $this->saveToCache();
                        }
                        $this->dataLoaded = true;
                }
                if ( ( $flags & self::LOAD_ALL ) && !$this->extraDataLoaded ) {
                        $this->loadExtraFromDB();
                }
        }

        /**
         * Upgrade a row if it needs it
         */
        function maybeUpgradeRow() {
                global $wgUpdateCompatibleMetadata;
                if ( wfReadOnly() ) {
                        return;
                }

                if ( is_null( $this->media_type ) ||
                        $this->mime == 'image/svg'
                ) {
                        $this->upgradeRow();
                        $this->upgraded = true;
                } else {
                        $handler = $this->getHandler();
                        if ( $handler ) {
                                $validity = $handler->isMetadataValid( $this, $this->getMetadata() );
                                if ( $validity === MediaHandler::METADATA_BAD
                                        || ( $validity === MediaHandler::METADATA_COMPATIBLE && $wgUpdateCompatibleMetadata )
                                ) {
                                        $this->upgradeRow();
                                        $this->upgraded = true;
                                }
                        }
                }
        }

        function getUpgraded() {
                return $this->upgraded;
        }

        /**
         * Fix assorted version-related problems with the image row by reloading it from the file
         */
        function upgradeRow() {
                wfProfileIn( __METHOD__ );

                $this->lock(); // begin

                $this->loadFromFile();

                # Don't destroy file info of missing files
                if ( !$this->fileExists ) {
                        wfDebug( __METHOD__ . ": file does not exist, aborting\n" );
                        wfProfileOut( __METHOD__ );
                        return;
                }

                $dbw = $this->repo->getMasterDB();
                list( $major, $minor ) = self::splitMime( $this->mime );

                if ( wfReadOnly() ) {
                        wfProfileOut( __METHOD__ );
                        return;
                }
                wfDebug( __METHOD__ . ': upgrading ' . $this->getName() . " to the current schema\n" );

                $dbw->update( 'image',
                        array(
                                'img_size' => $this->size, // sanity
                                'img_width' => $this->width,
                                'img_height' => $this->height,
                                'img_bits' => $this->bits,
                                'img_media_type' => $this->media_type,
                                'img_major_mime' => $major,
                                'img_minor_mime' => $minor,
                                'img_metadata' => $this->metadata,
                                'img_sha1' => $this->sha1,
                        ),
                        array( 'img_name' => $this->getName() ),
                        __METHOD__
                );

                $this->saveToCache();

                $this->unlock(); // done

                wfProfileOut( __METHOD__ );
        }

        /**
         * Set properties in this object to be equal to those given in the
         * associative array $info. Only cacheable fields can be set.
         * All fields *must* be set in $info except for getLazyCacheFields().
         *
         * If 'mime' is given, it will be split into major_mime/minor_mime.
         * If major_mime/minor_mime are given, $this->mime will also be set.
         */
        function setProps( $info ) {
                $this->dataLoaded = true;
                $fields = $this->getCacheFields( '' );
                $fields[] = 'fileExists';

                foreach ( $fields as $field ) {
                        if ( isset( $info[$field] ) ) {
                                $this->$field = $info[$field];
                        }
                }

                // Fix up mime fields
                if ( isset( $info['major_mime'] ) ) {
                        $this->mime = "{$info['major_mime']}/{$info['minor_mime']}";
                } elseif ( isset( $info['mime'] ) ) {
                        $this->mime = $info['mime'];
                        list( $this->major_mime, $this->minor_mime ) = self::splitMime( $this->mime );
                }
        }

        /** splitMime inherited */
        /** getName inherited */
        /** getTitle inherited */
        /** getURL inherited */
        /** getViewURL inherited */
        /** getPath inherited */
        /** isVisible inhereted */

        /**
         * @return bool
         */
        function isMissing() {
                if ( $this->missing === null ) {
                        list( $fileExists ) = $this->repo->fileExists( $this->getVirtualUrl() );
                        $this->missing = !$fileExists;
                }
                return $this->missing;
        }

        /**
         * Return the width of the image
         *
         * @param $page int
         * @return int
         */
        public function getWidth( $page = 1 ) {
                $this->load();

                if ( $this->isMultipage() ) {
                        $dim = $this->getHandler()->getPageDimensions( $this, $page );
                        if ( $dim ) {
                                return $dim['width'];
                        } else {
                                // For non-paged media, the false goes through an
                                // intval, turning failure into 0, so do same here.
                                return 0;
                        }
                } else {
                        return $this->width;
                }
        }

        /**
         * Return the height of the image
         *
         * @param $page int
         * @return int
         */
        public function getHeight( $page = 1 ) {
                $this->load();

                if ( $this->isMultipage() ) {
                        $dim = $this->getHandler()->getPageDimensions( $this, $page );
                        if ( $dim ) {
                                return $dim['height'];
                        } else {
                                // For non-paged media, the false goes through an
                                // intval, turning failure into 0, so do same here.
                                return 0;
                        }
                } else {
                        return $this->height;
                }
        }

        /**
         * Returns ID or name of user who uploaded the file
         *
         * @param string $type 'text' or 'id'
         * @return int|string
         */
        function getUser( $type = 'text' ) {
                $this->load();

                if ( $type == 'text' ) {
                        return $this->user_text;
                } elseif ( $type == 'id' ) {
                        return $this->user;
                }
        }

        /**
         * Get handler-specific metadata
         * @return string
         */
        function getMetadata() {
                $this->load( self::LOAD_ALL ); // large metadata is loaded in another step
                return $this->metadata;
        }

        /**
         * @return int
         */
        function getBitDepth() {
                $this->load();
                return $this->bits;
        }

        /**
         * Return the size of the image file, in bytes
         * @return int
         */
        public function getSize() {
                $this->load();
                return $this->size;
        }

        /**
         * Returns the mime type of the file.
         * @return string
         */
        function getMimeType() {
                $this->load();
                return $this->mime;
        }

        /**
         * Return the type of the media in the file.
         * Use the value returned by this function with the MEDIATYPE_xxx constants.
         * @return string
         */
        function getMediaType() {
                $this->load();
                return $this->media_type;
        }

        /** canRender inherited */
        /** mustRender inherited */
        /** allowInlineDisplay inherited */
        /** isSafeFile inherited */
        /** isTrustedFile inherited */

        /**
         * Returns true if the file exists on disk.
         * @return boolean Whether file exist on disk.
         */
        public function exists() {
                $this->load();
                return $this->fileExists;
        }

        /** getTransformScript inherited */
        /** getUnscaledThumb inherited */
        /** thumbName inherited */
        /** createThumb inherited */
        /** transform inherited */

        /**
         * Fix thumbnail files from 1.4 or before, with extreme prejudice
         * @todo : do we still care about this? Perhaps a maintenance script
         *        can be made instead. Enabling this code results in a serious
         *        RTT regression for wikis without 404 handling.
         */
        function migrateThumbFile( $thumbName ) {
                /* Old code for bug 2532
                $thumbDir = $this->getThumbPath();
                $thumbPath = "$thumbDir/$thumbName";
                if ( is_dir( $thumbPath ) ) {
                        // Directory where file should be
                        // This happened occasionally due to broken migration code in 1.5
                        // Rename to broken-*
                        for ( $i = 0; $i < 100; $i++ ) {
                                $broken = $this->repo->getZonePath( 'public' ) . "/broken-$i-$thumbName";
                                if ( !file_exists( $broken ) ) {
                                        rename( $thumbPath, $broken );
                                        break;
                                }
                        }
                        // Doesn't exist anymore
                        clearstatcache();
                }
                */

                /*
                if ( $this->repo->fileExists( $thumbDir ) ) {
                        // Delete file where directory should be
                        $this->repo->cleanupBatch( array( $thumbDir ) );
                }
                */
        }

        /** getHandler inherited */
        /** iconThumb inherited */
        /** getLastError inherited */

        /**
         * Get all thumbnail names previously generated for this file
         * @param string|bool $archiveName Name of an archive file, default false
         * @return array first element is the base dir, then files in that base dir.
         */
        function getThumbnails( $archiveName = false ) {
                if ( $archiveName ) {
                        $dir = $this->getArchiveThumbPath( $archiveName );
                } else {
                        $dir = $this->getThumbPath();
                }

                $backend = $this->repo->getBackend();
                $files = array( $dir );
                $iterator = $backend->getFileList( array( 'dir' => $dir ) );
                foreach ( $iterator as $file ) {
                        $files[] = $file;
                }

                return $files;
        }

        /**
         * Refresh metadata in memcached, but don't touch thumbnails or squid
         */
        function purgeMetadataCache() {
                $this->loadFromDB();
                $this->saveToCache();
                $this->purgeHistory();
        }

        /**
         * Purge the shared history (OldLocalFile) cache
         */
        function purgeHistory() {
                global $wgMemc;

                $hashedName = md5( $this->getName() );
                $oldKey = $this->repo->getSharedCacheKey( 'oldfile', $hashedName );

                // Must purge thumbnails for old versions too! bug 30192
                foreach ( $this->getHistory() as $oldFile ) {
                        $oldFile->purgeThumbnails();
                }

                if ( $oldKey ) {
                        $wgMemc->delete( $oldKey );
                }
        }

        /**
         * Delete all previously generated thumbnails, refresh metadata in memcached and purge the squid
         */
        function purgeCache( $options = array() ) {
                // Refresh metadata cache
                $this->purgeMetadataCache();

                // Delete thumbnails
                $this->purgeThumbnails( $options );

                // Purge squid cache for this file
                SquidUpdate::purge( array( $this->getURL() ) );
        }

        /**
         * Delete cached transformed files for an archived version only.
         * @param string $archiveName name of the archived file
         */
        function purgeOldThumbnails( $archiveName ) {
                global $wgUseSquid;
                wfProfileIn( __METHOD__ );

                // Get a list of old thumbnails and URLs
                $files = $this->getThumbnails( $archiveName );
                $dir = array_shift( $files );
                $this->purgeThumbList( $dir, $files );

                // Purge any custom thumbnail caches
                wfRunHooks( 'LocalFilePurgeThumbnails', array( $this, $archiveName ) );

                // Purge the squid
                if ( $wgUseSquid ) {
                        $urls = array();
                        foreach ( $files as $file ) {
                                $urls[] = $this->getArchiveThumbUrl( $archiveName, $file );
                        }
                        SquidUpdate::purge( $urls );
                }

                wfProfileOut( __METHOD__ );
        }

        /**
         * Delete cached transformed files for the current version only.
         */
        function purgeThumbnails( $options = array() ) {
                global $wgUseSquid;
                wfProfileIn( __METHOD__ );

                // Delete thumbnails
                $files = $this->getThumbnails();
                // Always purge all files from squid regardless of handler filters
                if ( $wgUseSquid ) {
                        $urls = array();
                        foreach ( $files as $file ) {
                                $urls[] = $this->getThumbUrl( $file );
                        }
                        array_shift( $urls ); // don't purge directory
                }

                // Give media handler a chance to filter the file purge list
                if ( !empty( $options['forThumbRefresh'] ) ) {
                        $handler = $this->getHandler();
                        if ( $handler ) {
                                $handler->filterThumbnailPurgeList( $files, $options );
                        }
                }

                $dir = array_shift( $files );
                $this->purgeThumbList( $dir, $files );

                // Purge any custom thumbnail caches
                wfRunHooks( 'LocalFilePurgeThumbnails', array( $this, false ) );

                // Purge the squid
                if ( $wgUseSquid ) {
                        SquidUpdate::purge( $urls );
                }

                wfProfileOut( __METHOD__ );
        }

        /**
         * Delete a list of thumbnails visible at urls
         * @param string $dir base dir of the files.
         * @param array $files of strings: relative filenames (to $dir)
         */
        protected function purgeThumbList( $dir, $files ) {
                $fileListDebug = strtr(
                        var_export( $files, true ),
                        array( "\n" => '' )
                );
                wfDebug( __METHOD__ . ": $fileListDebug\n" );

                $purgeList = array();
                foreach ( $files as $file ) {
                        # Check that the base file name is part of the thumb name
                        # This is a basic sanity check to avoid erasing unrelated directories
                        if ( strpos( $file, $this->getName() ) !== false
                                || strpos( $file, "-thumbnail" ) !== false // "short" thumb name
                        ) {
                                $purgeList[] = "{$dir}/{$file}";
                        }
                }

                # Delete the thumbnails
                $this->repo->quickPurgeBatch( $purgeList );
                # Clear out the thumbnail directory if empty
                $this->repo->quickCleanDir( $dir );
        }

        /** purgeDescription inherited */
        /** purgeEverything inherited */

        /**
         * @param $limit null
         * @param $start null
         * @param $end null
         * @param $inc bool
         * @return array
         */
        function getHistory( $limit = null, $start = null, $end = null, $inc = true ) {
                $dbr = $this->repo->getSlaveDB();
                $tables = array( 'oldimage' );
                $fields = OldLocalFile::selectFields();
                $conds = $opts = $join_conds = array();
                $eq = $inc ? '=' : '';
                $conds[] = "oi_name = " . $dbr->addQuotes( $this->title->getDBkey() );

                if ( $start ) {
                        $conds[] = "oi_timestamp <$eq " . $dbr->addQuotes( $dbr->timestamp( $start ) );
                }

                if ( $end ) {
                        $conds[] = "oi_timestamp >$eq " . $dbr->addQuotes( $dbr->timestamp( $end ) );
                }

                if ( $limit ) {
                        $opts['LIMIT'] = $limit;
                }

                // Search backwards for time > x queries
                $order = ( !$start && $end !== null ) ? 'ASC' : 'DESC';
                $opts['ORDER BY'] = "oi_timestamp $order";
                $opts['USE INDEX'] = array( 'oldimage' => 'oi_name_timestamp' );

                wfRunHooks( 'LocalFile::getHistory', array( &$this, &$tables, &$fields,
                        &$conds, &$opts, &$join_conds ) );

                $res = $dbr->select( $tables, $fields, $conds, __METHOD__, $opts, $join_conds );
                $r = array();

                foreach ( $res as $row ) {
                        if ( $this->repo->oldFileFromRowFactory ) {
                                $r[] = call_user_func( $this->repo->oldFileFromRowFactory, $row, $this->repo );
                        } else {
                                $r[] = OldLocalFile::newFromRow( $row, $this->repo );
                        }
                }

                if ( $order == 'ASC' ) {
                        $r = array_reverse( $r ); // make sure it ends up descending
                }

                return $r;
        }

        /**
         * Return the history of this file, line by line.
         * starts with current version, then old versions.
         * uses $this->historyLine to check which line to return:
         *  0      return line for current version
         *  1      query for old versions, return first one
         *  2, ... return next old version from above query
         * @return bool
         */
        public function nextHistoryLine() {
                # Polymorphic function name to distinguish foreign and local fetches
                $fname = get_class( $this ) . '::' . __FUNCTION__;

                $dbr = $this->repo->getSlaveDB();

                if ( $this->historyLine == 0 ) {// called for the first time, return line from cur
                        $this->historyRes = $dbr->select( 'image',
                                array(
                                        '*',
                                        "'' AS oi_archive_name",
                                        '0 as oi_deleted',
                                        'img_sha1'
                                ),
                                array( 'img_name' => $this->title->getDBkey() ),
                                $fname
                        );

                        if ( 0 == $dbr->numRows( $this->historyRes ) ) {
                                $this->historyRes = null;
                                return false;
                        }
                } elseif ( $this->historyLine == 1 ) {
                        $this->historyRes = $dbr->select( 'oldimage', '*',
                                array( 'oi_name' => $this->title->getDBkey() ),
                                $fname,
                                array( 'ORDER BY' => 'oi_timestamp DESC' )
                        );
                }
                $this->historyLine ++;

                return $dbr->fetchObject( $this->historyRes );
        }

        /**
         * Reset the history pointer to the first element of the history
         */
        public function resetHistory() {
                $this->historyLine = 0;

                if ( !is_null( $this->historyRes ) ) {
                        $this->historyRes = null;
                }
        }

        /** getHashPath inherited */
        /** getRel inherited */
        /** getUrlRel inherited */
        /** getArchiveRel inherited */
        /** getArchivePath inherited */
        /** getThumbPath inherited */
        /** getArchiveUrl inherited */
        /** getThumbUrl inherited */
        /** getArchiveVirtualUrl inherited */
        /** getThumbVirtualUrl inherited */
        /** isHashed inherited */

        /**
         * Upload a file and record it in the DB
         * @param string $srcPath source storage path, virtual URL, or filesystem path
         * @param string $comment upload description
         * @param string $pageText text to use for the new description page,
         *                  if a new description page is created
         * @param $flags Integer|bool: flags for publish()
         * @param array|bool $props File properties, if known. This can be used to reduce the
         *               upload time when uploading virtual URLs for which the file info
         *               is already known
         * @param string|bool $timestamp timestamp for img_timestamp, or false to use the current time
         * @param $user User|null: User object or null to use $wgUser
         *
         * @return FileRepoStatus object. On success, the value member contains the
         *     archive name, or an empty string if it was a new file.
         */
        function upload( $srcPath, $comment, $pageText, $flags = 0, $props = false, $timestamp = false, $user = null ) {
                global $wgContLang;

                if ( $this->getRepo()->getReadOnlyReason() !== false ) {
                        return $this->readOnlyFatalStatus();
                }

                if ( !$props ) {
                        wfProfileIn( __METHOD__ . '-getProps' );
                        if ( $this->repo->isVirtualUrl( $srcPath )
                                || FileBackend::isStoragePath( $srcPath ) )
                        {
                                $props = $this->repo->getFileProps( $srcPath );
                        } else {
                                $props = FSFile::getPropsFromPath( $srcPath );
                        }
                        wfProfileOut( __METHOD__ . '-getProps' );
                }

                $options = array();
                $handler = MediaHandler::getHandler( $props['mime'] );
                if ( $handler ) {
                        $options['headers'] = $handler->getStreamHeaders( $props['metadata'] );
                } else {
                        $options['headers'] = array();
                }

                // Trim spaces on user supplied text
                $comment = trim( $comment );

                // truncate nicely or the DB will do it for us
                // non-nicely (dangling multi-byte chars, non-truncated version in cache).
                $comment = $wgContLang->truncate( $comment, 255 );
                $this->lock(); // begin
                $status = $this->publish( $srcPath, $flags, $options );

                if ( $status->successCount > 0 ) {
                        # Essentially we are displacing any existing current file and saving
                        # a new current file at the old location. If just the first succeeded,
                        # we still need to displace the current DB entry and put in a new one.
                        if ( !$this->recordUpload2( $status->value, $comment, $pageText, $props, $timestamp, $user ) ) {
                                $status->fatal( 'filenotfound', $srcPath );
                        }
                }

                $this->unlock(); // done

                return $status;
        }

        /**
         * Record a file upload in the upload log and the image table
         * @param $oldver
         * @param $desc string
         * @param $license string
         * @param $copyStatus string
         * @param $source string
         * @param $watch bool
         * @param $timestamp string|bool
         * @param $user User object or null to use $wgUser
         * @return bool
         */
        function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '',
                $watch = false, $timestamp = false, User $user = null )
        {
                if ( !$user ) {
                        global $wgUser;
                        $user = $wgUser;
                }

                $pageText = SpecialUpload::getInitialPageText( $desc, $license, $copyStatus, $source );

                if ( !$this->recordUpload2( $oldver, $desc, $pageText, false, $timestamp, $user ) ) {
                        return false;
                }

                if ( $watch ) {
                        $user->addWatch( $this->getTitle() );
                }
                return true;
        }

        /**
         * Record a file upload in the upload log and the image table
         * @param $oldver
         * @param $comment string
         * @param $pageText string
         * @param $props bool|array
         * @param $timestamp bool|string
         * @param $user null|User
         * @return bool
         */
        function recordUpload2(
                $oldver, $comment, $pageText, $props = false, $timestamp = false, $user = null
        ) {
                wfProfileIn( __METHOD__ );

                if ( is_null( $user ) ) {
                        global $wgUser;
                        $user = $wgUser;
                }

                $dbw = $this->repo->getMasterDB();
                $dbw->begin( __METHOD__ );

                if ( !$props ) {
                        wfProfileIn( __METHOD__ . '-getProps' );
                        $props = $this->repo->getFileProps( $this->getVirtualUrl() );
                        wfProfileOut( __METHOD__ . '-getProps' );
                }

                if ( $timestamp === false ) {
                        $timestamp = $dbw->timestamp();
                }

                $props['description'] = $comment;
                $props['user'] = $user->getId();
                $props['user_text'] = $user->getName();
                $props['timestamp'] = wfTimestamp( TS_MW, $timestamp ); // DB -> TS_MW
                $this->setProps( $props );

                # Fail now if the file isn't there
                if ( !$this->fileExists ) {
                        wfDebug( __METHOD__ . ": File " . $this->getRel() . " went missing!\n" );
                        wfProfileOut( __METHOD__ );
                        return false;
                }

                $reupload = false;

                # Test to see if the row exists using INSERT IGNORE
                # This avoids race conditions by locking the row until the commit, and also
                # doesn't deadlock. SELECT FOR UPDATE causes a deadlock for every race condition.
                $dbw->insert( 'image',
                        array(
                                'img_name' => $this->getName(),
                                'img_size' => $this->size,
                                'img_width' => intval( $this->width ),
                                'img_height' => intval( $this->height ),
                                'img_bits' => $this->bits,
                                'img_media_type' => $this->media_type,
                                'img_major_mime' => $this->major_mime,
                                'img_minor_mime' => $this->minor_mime,
                                'img_timestamp' => $timestamp,
                                'img_description' => $comment,
                                'img_user' => $user->getId(),
                                'img_user_text' => $user->getName(),
                                'img_metadata' => $this->metadata,
                                'img_sha1' => $this->sha1
                        ),
                        __METHOD__,
                        'IGNORE'
                );
                if ( $dbw->affectedRows() == 0 ) {
                        # (bug 34993) Note: $oldver can be empty here, if the previous
                        # version of the file was broken. Allow registration of the new
                        # version to continue anyway, because that's better than having
                        # an image that's not fixable by user operations.

                        $reupload = true;
                        # Collision, this is an update of a file
                        # Insert previous contents into oldimage
                        $dbw->insertSelect( 'oldimage', 'image',
                                array(
                                        'oi_name'         => 'img_name',
                                        'oi_archive_name' => $dbw->addQuotes( $oldver ),
                                        'oi_size'         => 'img_size',
                                        'oi_width'        => 'img_width',
                                        'oi_height'       => 'img_height',
                                        'oi_bits'         => 'img_bits',
                                        'oi_timestamp'    => 'img_timestamp',
                                        'oi_description'  => 'img_description',
                                        'oi_user'         => 'img_user',
                                        'oi_user_text'    => 'img_user_text',
                                        'oi_metadata'     => 'img_metadata',
                                        'oi_media_type'   => 'img_media_type',
                                        'oi_major_mime'   => 'img_major_mime',
                                        'oi_minor_mime'   => 'img_minor_mime',
                                        'oi_sha1'         => 'img_sha1'
                                ),
                                array( 'img_name' => $this->getName() ),
                                __METHOD__
                        );

                        # Update the current image row
                        $dbw->update( 'image',
                                array( /* SET */
                                        'img_size'        => $this->size,
                                        'img_width'       => intval( $this->width ),
                                        'img_height'      => intval( $this->height ),
                                        'img_bits'        => $this->bits,
                                        'img_media_type'  => $this->media_type,
                                        'img_major_mime'  => $this->major_mime,
                                        'img_minor_mime'  => $this->minor_mime,
                                        'img_timestamp'   => $timestamp,
                                        'img_description' => $comment,
                                        'img_user'        => $user->getId(),
                                        'img_user_text'   => $user->getName(),
                                        'img_metadata'    => $this->metadata,
                                        'img_sha1'        => $this->sha1
                                ),
                                array( 'img_name' => $this->getName() ),
                                __METHOD__
                        );
                } else {
                        # This is a new file, so update the image count
                        DeferredUpdates::addUpdate( SiteStatsUpdate::factory( array( 'images' => 1 ) ) );
                }

                $descTitle = $this->getTitle();
                $wikiPage = new WikiFilePage( $descTitle );
                $wikiPage->setFile( $this );

                # Add the log entry
                $action = $reupload ? 'overwrite' : 'upload';

                $logEntry = new ManualLogEntry( 'upload', $action );
                $logEntry->setPerformer( $user );
                $logEntry->setComment( $comment );
                $logEntry->setTarget( $descTitle );

                // Allow people using the api to associate log entries with the upload.
                // Log has a timestamp, but sometimes different from upload timestamp.
                $logEntry->setParameters(
                        array(
                                'img_sha1' => $this->sha1,
                                'img_timestamp' => $timestamp,
                        )
                );
                // Note we keep $logId around since during new image
                // creation, page doesn't exist yet, so log_page = 0
                // but we want it to point to the page we're making,
                // so we later modify the log entry.
                // For a similar reason, we avoid making an RC entry
                // now and wait until the page exists.
                $logId = $logEntry->insert();

                $exists = $descTitle->exists();
                if ( $exists ) {
                        // Page exists, do RC entry now (otherwise we wait for later).
                        $logEntry->publish( $logId );
                }
                wfProfileIn( __METHOD__ . '-edit' );

                if ( $exists ) {
                        # Create a null revision
                        $latest = $descTitle->getLatestRevID();
                        $editSummary = LogFormatter::newFromEntry( $logEntry )->getPlainActionText();

                        $nullRevision = Revision::newNullRevision(
                                $dbw,
                                $descTitle->getArticleID(),
                                $editSummary,
                                false
                        );
                        if ( !is_null( $nullRevision ) ) {
                                $nullRevision->insertOn( $dbw );

                                wfRunHooks( 'NewRevisionFromEditComplete', array( $wikiPage, $nullRevision, $latest, $user ) );
                                $wikiPage->updateRevisionOn( $dbw, $nullRevision );
                        }
                }

                # Commit the transaction now, in case something goes wrong later
                # The most important thing is that files don't get lost, especially archives
                # NOTE: once we have support for nested transactions, the commit may be moved
                #       to after $wikiPage->doEdit has been called.
                $dbw->commit( __METHOD__ );

                if ( $exists ) {
                        # Invalidate the cache for the description page
                        $descTitle->invalidateCache();
                        $descTitle->purgeSquid();
                } else {
                        # New file; create the description page.
                        # There's already a log entry, so don't make a second RC entry
                        # Squid and file cache for the description page are purged by doEditContent.
                        $content = ContentHandler::makeContent( $pageText, $descTitle );
                        $status = $wikiPage->doEditContent( $content, $comment, EDIT_NEW | EDIT_SUPPRESS_RC, false, $user );

                        $dbw->begin( __METHOD__ ); // XXX; doEdit() uses a transaction
                        // Now that the page exists, make an RC entry.
                        $logEntry->publish( $logId );
                        if ( isset( $status->value['revision'] ) ) {
                                $dbw->update( 'logging',
                                        array( 'log_page' => $status->value['revision']->getPage() ),
                                        array( 'log_id' => $logId ),
                                        __METHOD__
                                );
                        }
                        $dbw->commit( __METHOD__ ); // commit before anything bad can happen
                }


                wfProfileOut( __METHOD__ . '-edit' );

                # Save to cache and purge the squid
                # We shall not saveToCache before the commit since otherwise
                # in case of a rollback there is an usable file from memcached
                # which in fact doesn't really exist (bug 24978)
                $this->saveToCache();

                if ( $reupload ) {
                        # Delete old thumbnails
                        wfProfileIn( __METHOD__ . '-purge' );
                        $this->purgeThumbnails();
                        wfProfileOut( __METHOD__ . '-purge' );

                        # Remove the old file from the squid cache
                        SquidUpdate::purge( array( $this->getURL() ) );
                }

                # Hooks, hooks, the magic of hooks...
                wfProfileIn( __METHOD__ . '-hooks' );
                wfRunHooks( 'FileUpload', array( $this, $reupload, $descTitle->exists() ) );
                wfProfileOut( __METHOD__ . '-hooks' );

                # Invalidate cache for all pages using this file
                $update = new HTMLCacheUpdate( $this->getTitle(), 'imagelinks' );
                $update->doUpdate();
                if ( !$reupload ) {
                        LinksUpdate::queueRecursiveJobsForTable( $this->getTitle(), 'imagelinks' );
                }

                # Invalidate cache for all pages that redirects on this page
                $redirs = $this->getTitle()->getRedirectsHere();

                foreach ( $redirs as $redir ) {
                        if ( !$reupload && $redir->getNamespace() === NS_FILE ) {
                                LinksUpdate::queueRecursiveJobsForTable( $redir, 'imagelinks' );
                        }
                        $update = new HTMLCacheUpdate( $redir, 'imagelinks' );
                        $update->doUpdate();
                }

                wfProfileOut( __METHOD__ );
                return true;
        }

        /**
         * Move or copy a file to its public location. If a file exists at the
         * destination, move it to an archive. Returns a FileRepoStatus object with
         * the archive name in the "value" member on success.
         *
         * The archive name should be passed through to recordUpload for database
         * registration.
         *
         * @param string $srcPath local filesystem path to the source image
         * @param $flags Integer: a bitwise combination of:
         *     File::DELETE_SOURCE      Delete the source file, i.e. move rather than copy
         * @param array $options Optional additional parameters
         * @return FileRepoStatus object. On success, the value member contains the
         *     archive name, or an empty string if it was a new file.
         */
        function publish( $srcPath, $flags = 0, array $options = array() ) {
                return $this->publishTo( $srcPath, $this->getRel(), $flags, $options );
        }

        /**
         * Move or copy a file to a specified location. Returns a FileRepoStatus
         * object with the archive name in the "value" member on success.
         *
         * The archive name should be passed through to recordUpload for database
         * registration.
         *
         * @param string $srcPath local filesystem path to the source image
         * @param string $dstRel target relative path
         * @param $flags Integer: a bitwise combination of:
         *     File::DELETE_SOURCE      Delete the source file, i.e. move rather than copy
         * @param array $options Optional additional parameters
         * @return FileRepoStatus object. On success, the value member contains the
         *     archive name, or an empty string if it was a new file.
         */
        function publishTo( $srcPath, $dstRel, $flags = 0, array $options = array() ) {
                if ( $this->getRepo()->getReadOnlyReason() !== false ) {
                        return $this->readOnlyFatalStatus();
                }

                $this->lock(); // begin

                $archiveName = wfTimestamp( TS_MW ) . '!' . $this->getName();
                $archiveRel = 'archive/' . $this->getHashPath() . $archiveName;
                $flags = $flags & File::DELETE_SOURCE ? LocalRepo::DELETE_SOURCE : 0;
                $status = $this->repo->publish( $srcPath, $dstRel, $archiveRel, $flags, $options );

                if ( $status->value == 'new' ) {
                        $status->value = '';
                } else {
                        $status->value = $archiveName;
                }

                $this->unlock(); // done

                return $status;
        }

        /** getLinksTo inherited */
        /** getExifData inherited */
        /** isLocal inherited */
        /** wasDeleted inherited */

        /**
         * Move file to the new title
         *
         * Move current, old version and all thumbnails
         * to the new filename. Old file is deleted.
         *
         * Cache purging is done; checks for validity
         * and logging are caller's responsibility
         *
         * @param $target Title New file name
         * @return FileRepoStatus object.
         */
        function move( $target ) {
                if ( $this->getRepo()->getReadOnlyReason() !== false ) {
                        return $this->readOnlyFatalStatus();
                }

                wfDebugLog( 'imagemove', "Got request to move {$this->name} to " . $target->getText() );
                $batch = new LocalFileMoveBatch( $this, $target );

                $this->lock(); // begin
                $batch->addCurrent();
                $archiveNames = $batch->addOlds();
                $status = $batch->execute();
                $this->unlock(); // done

                wfDebugLog( 'imagemove', "Finished moving {$this->name}" );

                $this->purgeEverything();
                foreach ( $archiveNames as $archiveName ) {
                        $this->purgeOldThumbnails( $archiveName );
                }
                if ( $status->isOK() ) {
                        // Now switch the object
                        $this->title = $target;
                        // Force regeneration of the name and hashpath
                        unset( $this->name );
                        unset( $this->hashPath );
                        // Purge the new image
                        $this->purgeEverything();
                }

                return $status;
        }

        /**
         * Delete all versions of the file.
         *
         * Moves the files into an archive directory (or deletes them)
         * and removes the database rows.
         *
         * Cache purging is done; logging is caller's responsibility.
         *
         * @param $reason
         * @param $suppress
         * @return FileRepoStatus object.
         */
        function delete( $reason, $suppress = false ) {
                if ( $this->getRepo()->getReadOnlyReason() !== false ) {
                        return $this->readOnlyFatalStatus();
                }

                $batch = new LocalFileDeleteBatch( $this, $reason, $suppress );

                $this->lock(); // begin
                $batch->addCurrent();
                # Get old version relative paths
                $archiveNames = $batch->addOlds();
                $status = $batch->execute();
                $this->unlock(); // done

                if ( $status->isOK() ) {
                        DeferredUpdates::addUpdate( SiteStatsUpdate::factory( array( 'images' => -1 ) ) );
                }

                $this->purgeEverything();
                foreach ( $archiveNames as $archiveName ) {
                        $this->purgeOldThumbnails( $archiveName );
                }

                return $status;
        }

        /**
         * Delete an old version of the file.
         *
         * Moves the file into an archive directory (or deletes it)
         * and removes the database row.
         *
         * Cache purging is done; logging is caller's responsibility.
         *
         * @param $archiveName String
         * @param $reason String
         * @param $suppress Boolean
         * @throws MWException or FSException on database or file store failure
         * @return FileRepoStatus object.
         */
        function deleteOld( $archiveName, $reason, $suppress = false ) {
                if ( $this->getRepo()->getReadOnlyReason() !== false ) {
                        return $this->readOnlyFatalStatus();
                }

                $batch = new LocalFileDeleteBatch( $this, $reason, $suppress );

                $this->lock(); // begin
                $batch->addOld( $archiveName );
                $status = $batch->execute();
                $this->unlock(); // done

                $this->purgeOldThumbnails( $archiveName );
                if ( $status->isOK() ) {
                        $this->purgeDescription();
                        $this->purgeHistory();
                }

                return $status;
        }

        /**
         * Restore all or specified deleted revisions to the given file.
         * Permissions and logging are left to the caller.
         *
         * May throw database exceptions on error.
         *
         * @param array $versions set of record ids of deleted items to restore,
         *                    or empty to restore all revisions.
         * @param $unsuppress Boolean
         * @return FileRepoStatus
         */
        function restore( $versions = array(), $unsuppress = false ) {
                if ( $this->getRepo()->getReadOnlyReason() !== false ) {
                        return $this->readOnlyFatalStatus();
                }

                $batch = new LocalFileRestoreBatch( $this, $unsuppress );

                $this->lock(); // begin
                if ( !$versions ) {
                        $batch->addAll();
                } else {
                        $batch->addIds( $versions );
                }
                $status = $batch->execute();
                if ( $status->isGood() ) {
                        $cleanupStatus = $batch->cleanup();
                        $cleanupStatus->successCount = 0;
                        $cleanupStatus->failCount = 0;
                        $status->merge( $cleanupStatus );
                }
                $this->unlock(); // done

                return $status;
        }

        /** isMultipage inherited */
        /** pageCount inherited */
        /** scaleHeight inherited */
        /** getImageSize inherited */

        /**
         * Get the URL of the file description page.
         * @return String
         */
        function getDescriptionUrl() {
                return $this->title->getLocalURL();
        }

        /**
         * Get the HTML text of the description page
         * This is not used by ImagePage for local files, since (among other things)
         * it skips the parser cache.
         * @return bool|mixed
         */
        function getDescriptionText() {
                $revision = Revision::newFromTitle( $this->title, false, Revision::READ_NORMAL );
                if ( !$revision ) {
                        return false;
                }
                $content = $revision->getContent();
                if ( !$content ) {
                        return false;
                }
                $pout = $content->getParserOutput( $this->title, null, new ParserOptions() );
                return $pout->getText();
        }

        /**
         * @return string
         */
        function getDescription( $audience = self::FOR_PUBLIC, User $user = null ) {
                $this->load();
                if ( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_COMMENT ) ) {
                        return '';
                } elseif ( $audience == self::FOR_THIS_USER
                        && !$this->userCan( self::DELETED_COMMENT, $user ) )
                {
                        return '';
                } else {
                        return $this->description;
                }
        }

        /**
         * @return bool|string
         */
        function getTimestamp() {
                $this->load();
                return $this->timestamp;
        }

        /**
         * @return string
         */
        function getSha1() {
                $this->load();
                // Initialise now if necessary
                if ( $this->sha1 == '' && $this->fileExists ) {
                        $this->lock(); // begin

                        $this->sha1 = $this->repo->getFileSha1( $this->getPath() );
                        if ( !wfReadOnly() && strval( $this->sha1 ) != '' ) {
                                $dbw = $this->repo->getMasterDB();
                                $dbw->update( 'image',
                                        array( 'img_sha1' => $this->sha1 ),
                                        array( 'img_name' => $this->getName() ),
                                        __METHOD__ );
                                $this->saveToCache();
                        }

                        $this->unlock(); // done
                }

                return $this->sha1;
        }

        /**
         * @return bool Whether to cache in RepoGroup (this avoids OOMs)
         */
        function isCacheable() {
                $this->load();
                // If extra data (metadata) was not loaded then it must have been large
                return $this->extraDataLoaded
                        && strlen( serialize( $this->metadata ) ) <= self::CACHE_FIELD_MAX_LEN;
        }

        /**
         * Start a transaction and lock the image for update
         * Increments a reference counter if the lock is already held
         * @return boolean True if the image exists, false otherwise
         */
        function lock() {
                $dbw = $this->repo->getMasterDB();

                if ( !$this->locked ) {
                        if ( !$dbw->trxLevel() ) {
                                $dbw->begin( __METHOD__ );
                                $this->lockedOwnTrx = true;
                        }
                        $this->locked++;
                }

                return $dbw->selectField( 'image', '1',
                        array( 'img_name' => $this->getName() ), __METHOD__, array( 'FOR UPDATE' ) );
        }

        /**
         * Decrement the lock reference count. If the reference count is reduced to zero, commits
         * the transaction and thereby releases the image lock.
         */
        function unlock() {
                if ( $this->locked ) {
                        --$this->locked;
                        if ( !$this->locked && $this->lockedOwnTrx ) {
                                $dbw = $this->repo->getMasterDB();
                                $dbw->commit( __METHOD__ );
                                $this->lockedOwnTrx = false;
                        }
                }
        }

        /**
         * Roll back the DB transaction and mark the image unlocked
         */
        function unlockAndRollback() {
                $this->locked = false;
                $dbw = $this->repo->getMasterDB();
                $dbw->rollback( __METHOD__ );
                $this->lockedOwnTrx = false;
        }

        /**
         * @return Status
         */
        protected function readOnlyFatalStatus() {
                return $this->getRepo()->newFatal( 'filereadonlyerror', $this->getName(),
                        $this->getRepo()->getName(), $this->getRepo()->getReadOnlyReason() );
        }
} // LocalFile class

# ------------------------------------------------------------------------------

/**
 * Helper class for file deletion
 * @ingroup FileAbstraction
 */
class LocalFileDeleteBatch {

        /**
         * @var LocalFile
         */
        var $file;

        var $reason, $srcRels = array(), $archiveUrls = array(), $deletionBatch, $suppress;
        var $status;

        /**
         * @param $file File
         * @param $reason string
         * @param $suppress bool
         */
        function __construct( File $file, $reason = '', $suppress = false ) {
                $this->file = $file;
                $this->reason = $reason;
                $this->suppress = $suppress;
                $this->status = $file->repo->newGood();
        }

        function addCurrent() {
                $this->srcRels['.'] = $this->file->getRel();
        }

        /**
         * @param $oldName string
         */
        function addOld( $oldName ) {
                $this->srcRels[$oldName] = $this->file->getArchiveRel( $oldName );
                $this->archiveUrls[] = $this->file->getArchiveUrl( $oldName );
        }

        /**
         * Add the old versions of the image to the batch
         * @return Array List of archive names from old versions
         */
        function addOlds() {
                $archiveNames = array();

                $dbw = $this->file->repo->getMasterDB();
                $result = $dbw->select( 'oldimage',
                        array( 'oi_archive_name' ),
                        array( 'oi_name' => $this->file->getName() ),
                        __METHOD__
                );

                foreach ( $result as $row ) {
                        $this->addOld( $row->oi_archive_name );
                        $archiveNames[] = $row->oi_archive_name;
                }

                return $archiveNames;
        }

        /**
         * @return array
         */
        function getOldRels() {
                if ( !isset( $this->srcRels['.'] ) ) {
                        $oldRels =& $this->srcRels;
                        $deleteCurrent = false;
                } else {
                        $oldRels = $this->srcRels;
                        unset( $oldRels['.'] );
                        $deleteCurrent = true;
                }

                return array( $oldRels, $deleteCurrent );
        }

        /**
         * @return array
         */
        protected function getHashes() {
                $hashes = array();
                list( $oldRels, $deleteCurrent ) = $this->getOldRels();

                if ( $deleteCurrent ) {
                        $hashes['.'] = $this->file->getSha1();
                }

                if ( count( $oldRels ) ) {
                        $dbw = $this->file->repo->getMasterDB();
                        $res = $dbw->select(
                                'oldimage',
                                array( 'oi_archive_name', 'oi_sha1' ),
                                'oi_archive_name IN (' . $dbw->makeList( array_keys( $oldRels ) ) . ')',
                                __METHOD__
                        );

                        foreach ( $res as $row ) {
                                if ( rtrim( $row->oi_sha1, "\0" ) === '' ) {
                                        // Get the hash from the file
                                        $oldUrl = $this->file->getArchiveVirtualUrl( $row->oi_archive_name );
                                        $props = $this->file->repo->getFileProps( $oldUrl );

                                        if ( $props['fileExists'] ) {
                                                // Upgrade the oldimage row
                                                $dbw->update( 'oldimage',
                                                        array( 'oi_sha1' => $props['sha1'] ),
                                                        array( 'oi_name' => $this->file->getName(), 'oi_archive_name' => $row->oi_archive_name ),
                                                        __METHOD__ );
                                                $hashes[$row->oi_archive_name] = $props['sha1'];
                                        } else {
                                                $hashes[$row->oi_archive_name] = false;
                                        }
                                } else {
                                        $hashes[$row->oi_archive_name] = $row->oi_sha1;
                                }
                        }
                }

                $missing = array_diff_key( $this->srcRels, $hashes );

                foreach ( $missing as $name => $rel ) {
                        $this->status->error( 'filedelete-old-unregistered', $name );
                }

                foreach ( $hashes as $name => $hash ) {
                        if ( !$hash ) {
                                $this->status->error( 'filedelete-missing', $this->srcRels[$name] );
                                unset( $hashes[$name] );
                        }
                }

                return $hashes;
        }

        function doDBInserts() {
                global $wgUser;

                $dbw = $this->file->repo->getMasterDB();
                $encTimestamp = $dbw->addQuotes( $dbw->timestamp() );
                $encUserId = $dbw->addQuotes( $wgUser->getId() );
                $encReason = $dbw->addQuotes( $this->reason );
                $encGroup = $dbw->addQuotes( 'deleted' );
                $ext = $this->file->getExtension();
                $dotExt = $ext === '' ? '' : ".$ext";
                $encExt = $dbw->addQuotes( $dotExt );
                list( $oldRels, $deleteCurrent ) = $this->getOldRels();

                // Bitfields to further suppress the content
                if ( $this->suppress ) {
                        $bitfield = 0;
                        // This should be 15...
                        $bitfield |= Revision::DELETED_TEXT;
                        $bitfield |= Revision::DELETED_COMMENT;
                        $bitfield |= Revision::DELETED_USER;
                        $bitfield |= Revision::DELETED_RESTRICTED;
                } else {
                        $bitfield = 'oi_deleted';
                }

                if ( $deleteCurrent ) {
                        $concat = $dbw->buildConcat( array( "img_sha1", $encExt ) );
                        $where = array( 'img_name' => $this->file->getName() );
                        $dbw->insertSelect( 'filearchive', 'image',
                                array(
                                        'fa_storage_group' => $encGroup,
                                        'fa_storage_key'   => "CASE WHEN img_sha1='' THEN '' ELSE $concat END",
                                        'fa_deleted_user'      => $encUserId,
                                        'fa_deleted_timestamp' => $encTimestamp,
                                        'fa_deleted_reason'    => $encReason,
                                        'fa_deleted'           => $this->suppress ? $bitfield : 0,

                                        'fa_name'         => 'img_name',
                                        'fa_archive_name' => 'NULL',
                                        'fa_size'         => 'img_size',
                                        'fa_width'        => 'img_width',
                                        'fa_height'       => 'img_height',
                                        'fa_metadata'     => 'img_metadata',
                                        'fa_bits'         => 'img_bits',
                                        'fa_media_type'   => 'img_media_type',
                                        'fa_major_mime'   => 'img_major_mime',
                                        'fa_minor_mime'   => 'img_minor_mime',
                                        'fa_description'  => 'img_description',
                                        'fa_user'         => 'img_user',
                                        'fa_user_text'    => 'img_user_text',
                                        'fa_timestamp'    => 'img_timestamp',
                                        'fa_sha1'         => 'img_sha1',
                                ), $where, __METHOD__ );
                }

                if ( count( $oldRels ) ) {
                        $concat = $dbw->buildConcat( array( "oi_sha1", $encExt ) );
                        $where = array(
                                'oi_name' => $this->file->getName(),
                                'oi_archive_name IN (' . $dbw->makeList( array_keys( $oldRels ) ) . ')' );
                        $dbw->insertSelect( 'filearchive', 'oldimage',
                                array(
                                        'fa_storage_group' => $encGroup,
                                        'fa_storage_key'   => "CASE WHEN oi_sha1='' THEN '' ELSE $concat END",
                                        'fa_deleted_user'      => $encUserId,
                                        'fa_deleted_timestamp' => $encTimestamp,
                                        'fa_deleted_reason'    => $encReason,
                                        'fa_deleted'           => $this->suppress ? $bitfield : 'oi_deleted',

                                        'fa_name'         => 'oi_name',
                                        'fa_archive_name' => 'oi_archive_name',
                                        'fa_size'         => 'oi_size',
                                        'fa_width'        => 'oi_width',
                                        'fa_height'       => 'oi_height',
                                        'fa_metadata'     => 'oi_metadata',
                                        'fa_bits'         => 'oi_bits',
                                        'fa_media_type'   => 'oi_media_type',
                                        'fa_major_mime'   => 'oi_major_mime',
                                        'fa_minor_mime'   => 'oi_minor_mime',
                                        'fa_description'  => 'oi_description',
                                        'fa_user'         => 'oi_user',
                                        'fa_user_text'    => 'oi_user_text',
                                        'fa_timestamp'    => 'oi_timestamp',
                                        'fa_sha1'         => 'oi_sha1',
                                ), $where, __METHOD__ );
                }
        }

        function doDBDeletes() {
                $dbw = $this->file->repo->getMasterDB();
                list( $oldRels, $deleteCurrent ) = $this->getOldRels();

                if ( count( $oldRels ) ) {
                        $dbw->delete( 'oldimage',
                                array(
                                        'oi_name' => $this->file->getName(),
                                        'oi_archive_name' => array_keys( $oldRels )
                                ), __METHOD__ );
                }

                if ( $deleteCurrent ) {
                        $dbw->delete( 'image', array( 'img_name' => $this->file->getName() ), __METHOD__ );
                }
        }

        /**
         * Run the transaction
         * @return FileRepoStatus
         */
        function execute() {
                wfProfileIn( __METHOD__ );

                $this->file->lock();
                // Leave private files alone
                $privateFiles = array();
                list( $oldRels, ) = $this->getOldRels();
                $dbw = $this->file->repo->getMasterDB();

                if ( !empty( $oldRels ) ) {
                        $res = $dbw->select( 'oldimage',
                                array( 'oi_archive_name' ),
                                array( 'oi_name' => $this->file->getName(),
                                        'oi_archive_name IN (' . $dbw->makeList( array_keys( $oldRels ) ) . ')',
                                        $dbw->bitAnd( 'oi_deleted', File::DELETED_FILE ) => File::DELETED_FILE ),
                                __METHOD__ );

                        foreach ( $res as $row ) {
                                $privateFiles[$row->oi_archive_name] = 1;
                        }
                }
                // Prepare deletion batch
                $hashes = $this->getHashes();
                $this->deletionBatch = array();
                $ext = $this->file->getExtension();
                $dotExt = $ext === '' ? '' : ".$ext";

                foreach ( $this->srcRels as $name => $srcRel ) {
                        // Skip files that have no hash (missing source).
                        // Keep private files where they are.
                        if ( isset( $hashes[$name] ) && !array_key_exists( $name, $privateFiles ) ) {
                                $hash = $hashes[$name];
                                $key = $hash . $dotExt;
                                $dstRel = $this->file->repo->getDeletedHashPath( $key ) . $key;
                                $this->deletionBatch[$name] = array( $srcRel, $dstRel );
                        }
                }

                // Lock the filearchive rows so that the files don't get deleted by a cleanup operation
                // We acquire this lock by running the inserts now, before the file operations.
                //
                // This potentially has poor lock contention characteristics -- an alternative
                // scheme would be to insert stub filearchive entries with no fa_name and commit
                // them in a separate transaction, then run the file ops, then update the fa_name fields.
                $this->doDBInserts();

                // Removes non-existent file from the batch, so we don't get errors.
                $this->deletionBatch = $this->removeNonexistentFiles( $this->deletionBatch );

                // Execute the file deletion batch
                $status = $this->file->repo->deleteBatch( $this->deletionBatch );

                if ( !$status->isGood() ) {
                        $this->status->merge( $status );
                }

                if ( !$this->status->isOK() ) {
                        // Critical file deletion error
                        // Roll back inserts, release lock and abort
                        // TODO: delete the defunct filearchive rows if we are using a non-transactional DB
                        $this->file->unlockAndRollback();
                        wfProfileOut( __METHOD__ );
                        return $this->status;
                }

                // Delete image/oldimage rows
                $this->doDBDeletes();

                // Commit and return
                $this->file->unlock();
                wfProfileOut( __METHOD__ );

                return $this->status;
        }

        /**
         * Removes non-existent files from a deletion batch.
         * @param $batch array
         * @return array
         */
        function removeNonexistentFiles( $batch ) {
                $files = $newBatch = array();

                foreach ( $batch as $batchItem ) {
                        list( $src, ) = $batchItem;
                        $files[$src] = $this->file->repo->getVirtualUrl( 'public' ) . '/' . rawurlencode( $src );
                }

                $result = $this->file->repo->fileExistsBatch( $files );

                foreach ( $batch as $batchItem ) {
                        if ( $result[$batchItem[0]] ) {
                                $newBatch[] = $batchItem;
                        }
                }

                return $newBatch;
        }
}

# ------------------------------------------------------------------------------

/**
 * Helper class for file undeletion
 * @ingroup FileAbstraction
 */
class LocalFileRestoreBatch {
        /**
         * @var LocalFile
         */
        var $file;

        var $cleanupBatch, $ids, $all, $unsuppress = false;

        /**
         * @param $file File
         * @param $unsuppress bool
         */
        function __construct( File $file, $unsuppress = false ) {
                $this->file = $file;
                $this->cleanupBatch = $this->ids = array();
                $this->ids = array();
                $this->unsuppress = $unsuppress;
        }

        /**
         * Add a file by ID
         */
        function addId( $fa_id ) {
                $this->ids[] = $fa_id;
        }

        /**
         * Add a whole lot of files by ID
         */
        function addIds( $ids ) {
                $this->ids = array_merge( $this->ids, $ids );
        }

        /**
         * Add all revisions of the file
         */
        function addAll() {
                $this->all = true;
        }

        /**
         * Run the transaction, except the cleanup batch.
         * The cleanup batch should be run in a separate transaction, because it locks different
         * rows and there's no need to keep the image row locked while it's acquiring those locks
         * The caller may have its own transaction open.
         * So we save the batch and let the caller call cleanup()
         * @return FileRepoStatus
         */
        function execute() {
                global $wgLang;

                if ( !$this->all && !$this->ids ) {
                        // Do nothing
                        return $this->file->repo->newGood();
                }

                $exists = $this->file->lock();
                $dbw = $this->file->repo->getMasterDB();
                $status = $this->file->repo->newGood();

                // Fetch all or selected archived revisions for the file,
                // sorted from the most recent to the oldest.
                $conditions = array( 'fa_name' => $this->file->getName() );

                if ( !$this->all ) {
                        $conditions[] = 'fa_id IN (' . $dbw->makeList( $this->ids ) . ')';
                }

                $result = $dbw->select(
                        'filearchive',
                        ArchivedFile::selectFields(),
                        $conditions,
                        __METHOD__,
                        array( 'ORDER BY' => 'fa_timestamp DESC' )
                );

                $idsPresent = array();
                $storeBatch = array();
                $insertBatch = array();
                $insertCurrent = false;
                $deleteIds = array();
                $first = true;
                $archiveNames = array();

                foreach ( $result as $row ) {
                        $idsPresent[] = $row->fa_id;

                        if ( $row->fa_name != $this->file->getName() ) {
                                $status->error( 'undelete-filename-mismatch', $wgLang->timeanddate( $row->fa_timestamp ) );
                                $status->failCount++;
                                continue;
                        }

                        if ( $row->fa_storage_key == '' ) {
                                // Revision was missing pre-deletion
                                $status->error( 'undelete-bad-store-key', $wgLang->timeanddate( $row->fa_timestamp ) );
                                $status->failCount++;
                                continue;
                        }

                        $deletedRel = $this->file->repo->getDeletedHashPath( $row->fa_storage_key ) . $row->fa_storage_key;
                        $deletedUrl = $this->file->repo->getVirtualUrl() . '/deleted/' . $deletedRel;

                        if ( isset( $row->fa_sha1 ) ) {
                                $sha1 = $row->fa_sha1;
                        } else {
                                // old row, populate from key
                                $sha1 = LocalRepo::getHashFromKey( $row->fa_storage_key );
                        }

                        # Fix leading zero
                        if ( strlen( $sha1 ) == 32 && $sha1[0] == '0' ) {
                                $sha1 = substr( $sha1, 1 );
                        }

                        if ( is_null( $row->fa_major_mime ) || $row->fa_major_mime == 'unknown'
                                || is_null( $row->fa_minor_mime ) || $row->fa_minor_mime == 'unknown'
                                || is_null( $row->fa_media_type ) || $row->fa_media_type == 'UNKNOWN'
                                || is_null( $row->fa_metadata ) ) {
                                // Refresh our metadata
                                // Required for a new current revision; nice for older ones too. :)
                                $props = RepoGroup::singleton()->getFileProps( $deletedUrl );
                        } else {
                                $props = array(
                                        'minor_mime' => $row->fa_minor_mime,
                                        'major_mime' => $row->fa_major_mime,
                                        'media_type' => $row->fa_media_type,
                                        'metadata'   => $row->fa_metadata
                                );
                        }

                        if ( $first && !$exists ) {
                                // This revision will be published as the new current version
                                $destRel = $this->file->getRel();
                                $insertCurrent = array(
                                        'img_name'        => $row->fa_name,
                                        'img_size'        => $row->fa_size,
                                        'img_width'       => $row->fa_width,
                                        'img_height'      => $row->fa_height,
                                        'img_metadata'    => $props['metadata'],
                                        'img_bits'        => $row->fa_bits,
                                        'img_media_type'  => $props['media_type'],
                                        'img_major_mime'  => $props['major_mime'],
                                        'img_minor_mime'  => $props['minor_mime'],
                                        'img_description' => $row->fa_description,
                                        'img_user'        => $row->fa_user,
                                        'img_user_text'   => $row->fa_user_text,
                                        'img_timestamp'   => $row->fa_timestamp,
                                        'img_sha1'        => $sha1
                                );

                                // The live (current) version cannot be hidden!
                                if ( !$this->unsuppress && $row->fa_deleted ) {
                                        $storeBatch[] = array( $deletedUrl, 'public', $destRel );
                                        $this->cleanupBatch[] = $row->fa_storage_key;
                                }
                        } else {
                                $archiveName = $row->fa_archive_name;

                                if ( $archiveName == '' ) {
                                        // This was originally a current version; we
                                        // have to devise a new archive name for it.
                                        // Format is <timestamp of archiving>!<name>
                                        $timestamp = wfTimestamp( TS_UNIX, $row->fa_deleted_timestamp );

                                        do {
                                                $archiveName = wfTimestamp( TS_MW, $timestamp ) . '!' . $row->fa_name;
                                                $timestamp++;
                                        } while ( isset( $archiveNames[$archiveName] ) );
                                }

                                $archiveNames[$archiveName] = true;
                                $destRel = $this->file->getArchiveRel( $archiveName );
                                $insertBatch[] = array(
                                        'oi_name'         => $row->fa_name,
                                        'oi_archive_name' => $archiveName,
                                        'oi_size'         => $row->fa_size,
                                        'oi_width'        => $row->fa_width,
                                        'oi_height'       => $row->fa_height,
                                        'oi_bits'         => $row->fa_bits,
                                        'oi_description'  => $row->fa_description,
                                        'oi_user'         => $row->fa_user,
                                        'oi_user_text'    => $row->fa_user_text,
                                        'oi_timestamp'    => $row->fa_timestamp,
                                        'oi_metadata'     => $props['metadata'],
                                        'oi_media_type'   => $props['media_type'],
                                        'oi_major_mime'   => $props['major_mime'],
                                        'oi_minor_mime'   => $props['minor_mime'],
                                        'oi_deleted'      => $this->unsuppress ? 0 : $row->fa_deleted,
                                        'oi_sha1'         => $sha1 );
                        }

                        $deleteIds[] = $row->fa_id;

                        if ( !$this->unsuppress && $row->fa_deleted & File::DELETED_FILE ) {
                                // private files can stay where they are
                                $status->successCount++;
                        } else {
                                $storeBatch[] = array( $deletedUrl, 'public', $destRel );
                                $this->cleanupBatch[] = $row->fa_storage_key;
                        }

                        $first = false;
                }

                unset( $result );

                // Add a warning to the status object for missing IDs
                $missingIds = array_diff( $this->ids, $idsPresent );

                foreach ( $missingIds as $id ) {
                        $status->error( 'undelete-missing-filearchive', $id );
                }

                // Remove missing files from batch, so we don't get errors when undeleting them
                $storeBatch = $this->removeNonexistentFiles( $storeBatch );

                // Run the store batch
                // Use the OVERWRITE_SAME flag to smooth over a common error
                $storeStatus = $this->file->repo->storeBatch( $storeBatch, FileRepo::OVERWRITE_SAME );
                $status->merge( $storeStatus );

                if ( !$status->isGood() ) {
                        // Even if some files could be copied, fail entirely as that is the
                        // easiest thing to do without data loss
                        $this->cleanupFailedBatch( $storeStatus, $storeBatch );
                        $status->ok = false;
                        $this->file->unlock();

                        return $status;
                }

                // Run the DB updates
                // Because we have locked the image row, key conflicts should be rare.
                // If they do occur, we can roll back the transaction at this time with
                // no data loss, but leaving unregistered files scattered throughout the
                // public zone.
                // This is not ideal, which is why it's important to lock the image row.
                if ( $insertCurrent ) {
                        $dbw->insert( 'image', $insertCurrent, __METHOD__ );
                }

                if ( $insertBatch ) {
                        $dbw->insert( 'oldimage', $insertBatch, __METHOD__ );
                }

                if ( $deleteIds ) {
                        $dbw->delete( 'filearchive',
                                array( 'fa_id IN (' . $dbw->makeList( $deleteIds ) . ')' ),
                                __METHOD__ );
                }

                // If store batch is empty (all files are missing), deletion is to be considered successful
                if ( $status->successCount > 0 || !$storeBatch ) {
                        if ( !$exists ) {
                                wfDebug( __METHOD__ . " restored {$status->successCount} items, creating a new current\n" );

                                DeferredUpdates::addUpdate( SiteStatsUpdate::factory( array( 'images' => 1 ) ) );

                                $this->file->purgeEverything();
                        } else {
                                wfDebug( __METHOD__ . " restored {$status->successCount} as archived versions\n" );
                                $this->file->purgeDescription();
                                $this->file->purgeHistory();
                        }
                }

                $this->file->unlock();

                return $status;
        }

        /**
         * Removes non-existent files from a store batch.
         * @param $triplets array
         * @return array
         */
        function removeNonexistentFiles( $triplets ) {
                $files = $filteredTriplets = array();
                foreach ( $triplets as $file ) {
                        $files[$file[0]] = $file[0];
                }

                $result = $this->file->repo->fileExistsBatch( $files );

                foreach ( $triplets as $file ) {
                        if ( $result[$file[0]] ) {
                                $filteredTriplets[] = $file;
                        }
                }

                return $filteredTriplets;
        }

        /**
         * Removes non-existent files from a cleanup batch.
         * @param $batch array
         * @return array
         */
        function removeNonexistentFromCleanup( $batch ) {
                $files = $newBatch = array();
                $repo = $this->file->repo;

                foreach ( $batch as $file ) {
                        $files[$file] = $repo->getVirtualUrl( 'deleted' ) . '/' .
                                rawurlencode( $repo->getDeletedHashPath( $file ) . $file );
                }

                $result = $repo->fileExistsBatch( $files );

                foreach ( $batch as $file ) {
                        if ( $result[$file] ) {
                                $newBatch[] = $file;
                        }
                }

                return $newBatch;
        }

        /**
         * Delete unused files in the deleted zone.
         * This should be called from outside the transaction in which execute() was called.
         * @return FileRepoStatus
         */
        function cleanup() {
                if ( !$this->cleanupBatch ) {
                        return $this->file->repo->newGood();
                }

                $this->cleanupBatch = $this->removeNonexistentFromCleanup( $this->cleanupBatch );

                $status = $this->file->repo->cleanupDeletedBatch( $this->cleanupBatch );

                return $status;
        }

        /**
         * Cleanup a failed batch. The batch was only partially successful, so
         * rollback by removing all items that were succesfully copied.
         *
         * @param Status $storeStatus
         * @param array $storeBatch
         */
        function cleanupFailedBatch( $storeStatus, $storeBatch ) {
                $cleanupBatch = array();

                foreach ( $storeStatus->success as $i => $success ) {
                        // Check if this item of the batch was successfully copied
                        if ( $success ) {
                                // Item was successfully copied and needs to be removed again
                                // Extract ($dstZone, $dstRel) from the batch
                                $cleanupBatch[] = array( $storeBatch[$i][1], $storeBatch[$i][2] );
                        }
                }
                $this->file->repo->cleanupBatch( $cleanupBatch );
        }
}

# ------------------------------------------------------------------------------

/**
 * Helper class for file movement
 * @ingroup FileAbstraction
 */
class LocalFileMoveBatch {

        /**
         * @var LocalFile
         */
        var $file;

        /**
         * @var Title
         */
        var $target;

        var $cur, $olds, $oldCount, $archive;

        /**
         * @var DatabaseBase
         */
        var $db;

        /**
         * @param File $file
         * @param Title $target
         */
        function __construct( File $file, Title $target ) {
                $this->file = $file;
                $this->target = $target;
                $this->oldHash = $this->file->repo->getHashPath( $this->file->getName() );
                $this->newHash = $this->file->repo->getHashPath( $this->target->getDBkey() );
                $this->oldName = $this->file->getName();
                $this->newName = $this->file->repo->getNameFromTitle( $this->target );
                $this->oldRel = $this->oldHash . $this->oldName;
                $this->newRel = $this->newHash . $this->newName;
                $this->db = $file->getRepo()->getMasterDb();
        }

        /**
         * Add the current image to the batch
         */
        function addCurrent() {
                $this->cur = array( $this->oldRel, $this->newRel );
        }

        /**
         * Add the old versions of the image to the batch
         * @return Array List of archive names from old versions
         */
        function addOlds() {
                $archiveBase = 'archive';
                $this->olds = array();
                $this->oldCount = 0;
                $archiveNames = array();

                $result = $this->db->select( 'oldimage',
                        array( 'oi_archive_name', 'oi_deleted' ),
                        array( 'oi_name' => $this->oldName ),
                        __METHOD__
                );

                foreach ( $result as $row ) {
                        $archiveNames[] = $row->oi_archive_name;
                        $oldName = $row->oi_archive_name;
                        $bits = explode( '!', $oldName, 2 );

                        if ( count( $bits ) != 2 ) {
                                wfDebug( "Old file name missing !: '$oldName' \n" );
                                continue;
                        }

                        list( $timestamp, $filename ) = $bits;

                        if ( $this->oldName != $filename ) {
                                wfDebug( "Old file name doesn't match: '$oldName' \n" );
                                continue;
                        }

                        $this->oldCount++;

                        // Do we want to add those to oldCount?
                        if ( $row->oi_deleted & File::DELETED_FILE ) {
                                continue;
                        }

                        $this->olds[] = array(
                                "{$archiveBase}/{$this->oldHash}{$oldName}",
                                "{$archiveBase}/{$this->newHash}{$timestamp}!{$this->newName}"
                        );
                }

                return $archiveNames;
        }

        /**
         * Perform the move.
         * @return FileRepoStatus
         */
        function execute() {
                $repo = $this->file->repo;
                $status = $repo->newGood();

                $triplets = $this->getMoveTriplets();
                $triplets = $this->removeNonexistentFiles( $triplets );

                $this->file->lock(); // begin
                // Rename the file versions metadata in the DB.
                // This implicitly locks the destination file, which avoids race conditions.
                // If we moved the files from A -> C before DB updates, another process could
                // move files from B -> C at this point, causing storeBatch() to fail and thus
                // cleanupTarget() to trigger. It would delete the C files and cause data loss.
                $statusDb = $this->doDBUpdates();
                if ( !$statusDb->isGood() ) {
                        $this->file->unlockAndRollback();
                        $statusDb->ok = false;
                        return $statusDb;
                }
                wfDebugLog( 'imagemove', "Renamed {$this->file->getName()} in database: {$statusDb->successCount} successes, {$statusDb->failCount} failures" );

                // Copy the files into their new location.
                // If a prior process fataled copying or cleaning up files we tolerate any
                // of the existing files if they are identical to the ones being stored.
                $statusMove = $repo->storeBatch( $triplets, FileRepo::OVERWRITE_SAME );
                wfDebugLog( 'imagemove', "Moved files for {$this->file->getName()}: {$statusMove->successCount} successes, {$statusMove->failCount} failures" );
                if ( !$statusMove->isGood() ) {
                        // Delete any files copied over (while the destination is still locked)
                        $this->cleanupTarget( $triplets );
                        $this->file->unlockAndRollback(); // unlocks the destination
                        wfDebugLog( 'imagemove', "Error in moving files: " . $statusMove->getWikiText() );
                        $statusMove->ok = false;
                        return $statusMove;
                }
                $this->file->unlock(); // done

                // Everything went ok, remove the source files
                $this->cleanupSource( $triplets );

                $status->merge( $statusDb );
                $status->merge( $statusMove );

                return $status;
        }

        /**
         * Do the database updates and return a new FileRepoStatus indicating how
         * many rows where updated.
         *
         * @return FileRepoStatus
         */
        function doDBUpdates() {
                $repo = $this->file->repo;
                $status = $repo->newGood();
                $dbw = $this->db;

                // Update current image
                $dbw->update(
                        'image',
                        array( 'img_name' => $this->newName ),
                        array( 'img_name' => $this->oldName ),
                        __METHOD__
                );

                if ( $dbw->affectedRows() ) {
                        $status->successCount++;
                } else {
                        $status->failCount++;
                        $status->fatal( 'imageinvalidfilename' );
                        return $status;
                }

                // Update old images
                $dbw->update(
                        'oldimage',
                        array(
                                'oi_name' => $this->newName,
                                'oi_archive_name = ' . $dbw->strreplace( 'oi_archive_name',
                                        $dbw->addQuotes( $this->oldName ), $dbw->addQuotes( $this->newName ) ),
                        ),
                        array( 'oi_name' => $this->oldName ),
                        __METHOD__
                );

                $affected = $dbw->affectedRows();
                $total = $this->oldCount;
                $status->successCount += $affected;
                // Bug 34934: $total is based on files that actually exist.
                // There may be more DB rows than such files, in which case $affected
                // can be greater than $total. We use max() to avoid negatives here.
                $status->failCount += max( 0, $total - $affected );
                if ( $status->failCount ) {
                        $status->error( 'imageinvalidfilename' );
                }

                return $status;
        }

        /**
         * Generate triplets for FileRepo::storeBatch().
         * @return array
         */
        function getMoveTriplets() {
                $moves = array_merge( array( $this->cur ), $this->olds );
                $triplets = array(); // The format is: (srcUrl, destZone, destUrl)

                foreach ( $moves as $move ) {
                        // $move: (oldRelativePath, newRelativePath)
                        $srcUrl = $this->file->repo->getVirtualUrl() . '/public/' . rawurlencode( $move[0] );
                        $triplets[] = array( $srcUrl, 'public', $move[1] );
                        wfDebugLog( 'imagemove', "Generated move triplet for {$this->file->getName()}: {$srcUrl} :: public :: {$move[1]}" );
                }

                return $triplets;
        }

        /**
         * Removes non-existent files from move batch.
         * @param $triplets array
         * @return array
         */
        function removeNonexistentFiles( $triplets ) {
                $files = array();

                foreach ( $triplets as $file ) {
                        $files[$file[0]] = $file[0];
                }

                $result = $this->file->repo->fileExistsBatch( $files );
                $filteredTriplets = array();

                foreach ( $triplets as $file ) {
                        if ( $result[$file[0]] ) {
                                $filteredTriplets[] = $file;
                        } else {
                                wfDebugLog( 'imagemove', "File {$file[0]} does not exist" );
                        }
                }

                return $filteredTriplets;
        }

        /**
         * Cleanup a partially moved array of triplets by deleting the target
         * files. Called if something went wrong half way.
         */
        function cleanupTarget( $triplets ) {
                // Create dest pairs from the triplets
                $pairs = array();
                foreach ( $triplets as $triplet ) {
                        // $triplet: (old source virtual URL, dst zone, dest rel)
                        $pairs[] = array( $triplet[1], $triplet[2] );
                }

                $this->file->repo->cleanupBatch( $pairs );
        }

        /**
         * Cleanup a fully moved array of triplets by deleting the source files.
         * Called at the end of the move process if everything else went ok.
         */
        function cleanupSource( $triplets ) {
                // Create source file names from the triplets
                $files = array();
                foreach ( $triplets as $triplet ) {
                        $files[] = $triplet[0];
                }

                $this->file->repo->cleanupBatch( $files );
        }
}