includes/Revision.php

   1 <?php
   2 /**
   3  * Representation of a page version.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 /**
  24  * @todo document
  25  */
  26 class Revision implements IDBAccessObject {
  27         protected $mId;
  28
  29         /**
  30          * @var int|null
  31          */
  32         protected $mPage;
  33         protected $mUserText;
  34         protected $mOrigUserText;
  35         protected $mUser;
  36         protected $mMinorEdit;
  37         protected $mTimestamp;
  38         protected $mDeleted;
  39         protected $mSize;
  40         protected $mSha1;
  41         protected $mParentId;
  42         protected $mComment;
  43         protected $mText;
  44         protected $mTextId;
  45
  46         /**
  47          * @var stdClass|null
  48          */
  49         protected $mTextRow;
  50
  51         /**
  52          * @var null|Title
  53          */
  54         protected $mTitle;
  55         protected $mCurrent;
  56         protected $mContentModel;
  57         protected $mContentFormat;
  58
  59         /**
  60          * @var Content|null|bool
  61          */
  62         protected $mContent;
  63
  64         /**
  65          * @var null|ContentHandler
  66          */
  67         protected $mContentHandler;
  68
  69         /**
  70          * @var int
  71          */
  72         protected $mQueryFlags = 0;
  73
  74         // Revision deletion constants
  75         const DELETED_TEXT = 1;
  76         const DELETED_COMMENT = 2;
  77         const DELETED_USER = 4;
  78         const DELETED_RESTRICTED = 8;
  79         const SUPPRESSED_USER = 12; // convenience
  80
  81         // Audience options for accessors
  82         const FOR_PUBLIC = 1;
  83         const FOR_THIS_USER = 2;
  84         const RAW = 3;
  85
  86         /**
  87          * Load a page revision from a given revision ID number.
  88          * Returns null if no such revision can be found.
  89          *
  90          * $flags include:
  91          *      Revision::READ_LATEST  : Select the data from the master
  92          *      Revision::READ_LOCKING : Select & lock the data from the master
  93          *
  94          * @param int $id
  95          * @param int $flags (optional)
  96          * @return Revision|null
  97          */
  98         public static function newFromId( $id, $flags = 0 ) {
  99                 return self::newFromConds( array( 'rev_id' => intval( $id ) ), $flags );
 100         }
 101
 102         /**
 103          * Load either the current, or a specified, revision
 104          * that's attached to a given title. If not attached
 105          * to that title, will return null.
 106          *
 107          * $flags include:
 108          *      Revision::READ_LATEST  : Select the data from the master
 109          *      Revision::READ_LOCKING : Select & lock the data from the master
 110          *
 111          * @param Title $title
 112          * @param int $id (optional)
 113          * @param int $flags Bitfield (optional)
 114          * @return Revision|null
 115          */
 116         public static function newFromTitle( $title, $id = 0, $flags = 0 ) {
 117                 $conds = array(
 118                         'page_namespace' => $title->getNamespace(),
 119                         'page_title' => $title->getDBkey()
 120                 );
 121                 if ( $id ) {
 122                         // Use the specified ID
 123                         $conds['rev_id'] = $id;
 124                         return self::newFromConds( $conds, (int)$flags );
 125                 } else {
 126                         // Use a join to get the latest revision
 127                         $conds[] = 'rev_id=page_latest';
 128                         $db = wfGetDB( ( $flags & self::READ_LATEST ) ? DB_MASTER : DB_SLAVE );
 129                         return self::loadFromConds( $db, $conds, $flags );
 130                 }
 131         }
 132
 133         /**
 134          * Load either the current, or a specified, revision
 135          * that's attached to a given page ID.
 136          * Returns null if no such revision can be found.
 137          *
 138          * $flags include:
 139          *      Revision::READ_LATEST  : Select the data from the master (since 1.20)
 140          *      Revision::READ_LOCKING : Select & lock the data from the master
 141          *
 142          * @param int $pageId
 143          * @param int $revId (optional)
 144          * @param int $flags Bitfield (optional)
 145          * @return Revision|null
 146          */
 147         public static function newFromPageId( $pageId, $revId = 0, $flags = 0 ) {
 148                 $conds = array( 'page_id' => $pageId );
 149                 if ( $revId ) {
 150                         $conds['rev_id'] = $revId;
 151                 } else {
 152                         // Use a join to get the latest revision
 153                         $conds[] = 'rev_id = page_latest';
 154                 }
 155                 return self::newFromConds( $conds, (int)$flags );
 156         }
 157
 158         /**
 159          * Make a fake revision object from an archive table row. This is queried
 160          * for permissions or even inserted (as in Special:Undelete)
 161          * @todo FIXME: Should be a subclass for RevisionDelete. [TS]
 162          *
 163          * @param object $row
 164          * @param array $overrides
 165          *
 166          * @throws MWException
 167          * @return Revision
 168          */
 169         public static function newFromArchiveRow( $row, $overrides = array() ) {
 170                 global $wgContentHandlerUseDB;
 171
 172                 $attribs = $overrides + array(
 173                         'page'       => isset( $row->ar_page_id ) ? $row->ar_page_id : null,
 174                         'id'         => isset( $row->ar_rev_id ) ? $row->ar_rev_id : null,
 175                         'comment'    => $row->ar_comment,
 176                         'user'       => $row->ar_user,
 177                         'user_text'  => $row->ar_user_text,
 178                         'timestamp'  => $row->ar_timestamp,
 179                         'minor_edit' => $row->ar_minor_edit,
 180                         'text_id'    => isset( $row->ar_text_id ) ? $row->ar_text_id : null,
 181                         'deleted'    => $row->ar_deleted,
 182                         'len'        => $row->ar_len,
 183                         'sha1'       => isset( $row->ar_sha1 ) ? $row->ar_sha1 : null,
 184                         'content_model'   => isset( $row->ar_content_model ) ? $row->ar_content_model : null,
 185                         'content_format'  => isset( $row->ar_content_format ) ? $row->ar_content_format : null,
 186                 );
 187
 188                 if ( !$wgContentHandlerUseDB ) {
 189                         unset( $attribs['content_model'] );
 190                         unset( $attribs['content_format'] );
 191                 }
 192
 193                 if ( !isset( $attribs['title'] )
 194                         && isset( $row->ar_namespace )
 195                         && isset( $row->ar_title ) ) {
 196
 197                         $attribs['title'] = Title::makeTitle( $row->ar_namespace, $row->ar_title );
 198                 }
 199
 200                 if ( isset( $row->ar_text ) && !$row->ar_text_id ) {
 201                         // Pre-1.5 ar_text row
 202                         $attribs['text'] = self::getRevisionText( $row, 'ar_' );
 203                         if ( $attribs['text'] === false ) {
 204                                 throw new MWException( 'Unable to load text from archive row (possibly bug 22624)' );
 205                         }
 206                 }
 207                 return new self( $attribs );
 208         }
 209
 210         /**
 211          * @since 1.19
 212          *
 213          * @param object $row
 214          * @return Revision
 215          */
 216         public static function newFromRow( $row ) {
 217                 return new self( $row );
 218         }
 219
 220         /**
 221          * Load a page revision from a given revision ID number.
 222          * Returns null if no such revision can be found.
 223          *
 224          * @param DatabaseBase $db
 225          * @param int $id
 226          * @return Revision|null
 227          */
 228         public static function loadFromId( $db, $id ) {
 229                 return self::loadFromConds( $db, array( 'rev_id' => intval( $id ) ) );
 230         }
 231
 232         /**
 233          * Load either the current, or a specified, revision
 234          * that's attached to a given page. If not attached
 235          * to that page, will return null.
 236          *
 237          * @param DatabaseBase $db
 238          * @param int $pageid
 239          * @param int $id
 240          * @return Revision|null
 241          */
 242         public static function loadFromPageId( $db, $pageid, $id = 0 ) {
 243                 $conds = array( 'rev_page' => intval( $pageid ), 'page_id' => intval( $pageid ) );
 244                 if ( $id ) {
 245                         $conds['rev_id'] = intval( $id );
 246                 } else {
 247                         $conds[] = 'rev_id=page_latest';
 248                 }
 249                 return self::loadFromConds( $db, $conds );
 250         }
 251
 252         /**
 253          * Load either the current, or a specified, revision
 254          * that's attached to a given page. If not attached
 255          * to that page, will return null.
 256          *
 257          * @param DatabaseBase $db
 258          * @param Title $title
 259          * @param int $id
 260          * @return Revision|null
 261          */
 262         public static function loadFromTitle( $db, $title, $id = 0 ) {
 263                 if ( $id ) {
 264                         $matchId = intval( $id );
 265                 } else {
 266                         $matchId = 'page_latest';
 267                 }
 268                 return self::loadFromConds( $db,
 269                         array(
 270                                 "rev_id=$matchId",
 271                                 'page_namespace' => $title->getNamespace(),
 272                                 'page_title' => $title->getDBkey()
 273                         )
 274                 );
 275         }
 276
 277         /**
 278          * Load the revision for the given title with the given timestamp.
 279          * WARNING: Timestamps may in some circumstances not be unique,
 280          * so this isn't the best key to use.
 281          *
 282          * @param DatabaseBase $db
 283          * @param Title $title
 284          * @param string $timestamp
 285          * @return Revision|null
 286          */
 287         public static function loadFromTimestamp( $db, $title, $timestamp ) {
 288                 return self::loadFromConds( $db,
 289                         array(
 290                                 'rev_timestamp' => $db->timestamp( $timestamp ),
 291                                 'page_namespace' => $title->getNamespace(),
 292                                 'page_title' => $title->getDBkey()
 293                         )
 294                 );
 295         }
 296
 297         /**
 298          * Given a set of conditions, fetch a revision.
 299          *
 300          * @param array $conditions
 301          * @param int $flags (optional)
 302          * @return Revision|null
 303          */
 304         private static function newFromConds( $conditions, $flags = 0 ) {
 305                 $db = wfGetDB( ( $flags & self::READ_LATEST ) ? DB_MASTER : DB_SLAVE );
 306                 $rev = self::loadFromConds( $db, $conditions, $flags );
 307                 if ( $rev === null && wfGetLB()->getServerCount() > 1 ) {
 308                         if ( !( $flags & self::READ_LATEST ) ) {
 309                                 $dbw = wfGetDB( DB_MASTER );
 310                                 $rev = self::loadFromConds( $dbw, $conditions, $flags );
 311                         }
 312                 }
 313                 if ( $rev ) {
 314                         $rev->mQueryFlags = $flags;
 315                 }
 316                 return $rev;
 317         }
 318
 319         /**
 320          * Given a set of conditions, fetch a revision from
 321          * the given database connection.
 322          *
 323          * @param DatabaseBase $db
 324          * @param array $conditions
 325          * @param int $flags (optional)
 326          * @return Revision|null
 327          */
 328         private static function loadFromConds( $db, $conditions, $flags = 0 ) {
 329                 $res = self::fetchFromConds( $db, $conditions, $flags );
 330                 if ( $res ) {
 331                         $row = $res->fetchObject();
 332                         if ( $row ) {
 333                                 $ret = new Revision( $row );
 334                                 return $ret;
 335                         }
 336                 }
 337                 $ret = null;
 338                 return $ret;
 339         }
 340
 341         /**
 342          * Return a wrapper for a series of database rows to
 343          * fetch all of a given page's revisions in turn.
 344          * Each row can be fed to the constructor to get objects.
 345          *
 346          * @param Title $title
 347          * @return ResultWrapper
 348          */
 349         public static function fetchRevision( $title ) {
 350                 return self::fetchFromConds(
 351                         wfGetDB( DB_SLAVE ),
 352                         array(
 353                                 'rev_id=page_latest',
 354                                 'page_namespace' => $title->getNamespace(),
 355                                 'page_title' => $title->getDBkey()
 356                         )
 357                 );
 358         }
 359
 360         /**
 361          * Given a set of conditions, return a ResultWrapper
 362          * which will return matching database rows with the
 363          * fields necessary to build Revision objects.
 364          *
 365          * @param DatabaseBase $db
 366          * @param array $conditions
 367          * @param int $flags (optional)
 368          * @return ResultWrapper
 369          */
 370         private static function fetchFromConds( $db, $conditions, $flags = 0 ) {
 371                 $fields = array_merge(
 372                         self::selectFields(),
 373                         self::selectPageFields(),
 374                         self::selectUserFields()
 375                 );
 376                 $options = array( 'LIMIT' => 1 );
 377                 if ( ( $flags & self::READ_LOCKING ) == self::READ_LOCKING ) {
 378                         $options[] = 'FOR UPDATE';
 379                 }
 380                 return $db->select(
 381                         array( 'revision', 'page', 'user' ),
 382                         $fields,
 383                         $conditions,
 384                         __METHOD__,
 385                         $options,
 386                         array( 'page' => self::pageJoinCond(), 'user' => self::userJoinCond() )
 387                 );
 388         }
 389
 390         /**
 391          * Return the value of a select() JOIN conds array for the user table.
 392          * This will get user table rows for logged-in users.
 393          * @since 1.19
 394          * @return array
 395          */
 396         public static function userJoinCond() {
 397                 return array( 'LEFT JOIN', array( 'rev_user != 0', 'user_id = rev_user' ) );
 398         }
 399
 400         /**
 401          * Return the value of a select() page conds array for the page table.
 402          * This will assure that the revision(s) are not orphaned from live pages.
 403          * @since 1.19
 404          * @return array
 405          */
 406         public static function pageJoinCond() {
 407                 return array( 'INNER JOIN', array( 'page_id = rev_page' ) );
 408         }
 409
 410         /**
 411          * Return the list of revision fields that should be selected to create
 412          * a new revision.
 413          * @return array
 414          */
 415         public static function selectFields() {
 416                 global $wgContentHandlerUseDB;
 417
 418                 $fields = array(
 419                         'rev_id',
 420                         'rev_page',
 421                         'rev_text_id',
 422                         'rev_timestamp',
 423                         'rev_comment',
 424                         'rev_user_text',
 425                         'rev_user',
 426                         'rev_minor_edit',
 427                         'rev_deleted',
 428                         'rev_len',
 429                         'rev_parent_id',
 430                         'rev_sha1',
 431                 );
 432
 433                 if ( $wgContentHandlerUseDB ) {
 434                         $fields[] = 'rev_content_format';
 435                         $fields[] = 'rev_content_model';
 436                 }
 437
 438                 return $fields;
 439         }
 440
 441         /**
 442          * Return the list of revision fields that should be selected to create
 443          * a new revision from an archive row.
 444          * @return array
 445          */
 446         public static function selectArchiveFields() {
 447                 global $wgContentHandlerUseDB;
 448                 $fields = array(
 449                         'ar_id',
 450                         'ar_page_id',
 451                         'ar_rev_id',
 452                         'ar_text',
 453                         'ar_text_id',
 454                         'ar_timestamp',
 455                         'ar_comment',
 456                         'ar_user_text',
 457                         'ar_user',
 458                         'ar_minor_edit',
 459                         'ar_deleted',
 460                         'ar_len',
 461                         'ar_parent_id',
 462                         'ar_sha1',
 463                 );
 464
 465                 if ( $wgContentHandlerUseDB ) {
 466                         $fields[] = 'ar_content_format';
 467                         $fields[] = 'ar_content_model';
 468                 }
 469                 return $fields;
 470         }
 471
 472         /**
 473          * Return the list of text fields that should be selected to read the
 474          * revision text
 475          * @return array
 476          */
 477         public static function selectTextFields() {
 478                 return array(
 479                         'old_text',
 480                         'old_flags'
 481                 );
 482         }
 483
 484         /**
 485          * Return the list of page fields that should be selected from page table
 486          * @return array
 487          */
 488         public static function selectPageFields() {
 489                 return array(
 490                         'page_namespace',
 491                         'page_title',
 492                         'page_id',
 493                         'page_latest',
 494                         'page_is_redirect',
 495                         'page_len',
 496                 );
 497         }
 498
 499         /**
 500          * Return the list of user fields that should be selected from user table
 501          * @return array
 502          */
 503         public static function selectUserFields() {
 504                 return array( 'user_name' );
 505         }
 506
 507         /**
 508          * Do a batched query to get the parent revision lengths
 509          * @param DatabaseBase $db
 510          * @param array $revIds
 511          * @return array
 512          */
 513         public static function getParentLengths( $db, array $revIds ) {
 514                 $revLens = array();
 515                 if ( !$revIds ) {
 516                         return $revLens; // empty
 517                 }
 518                 wfProfileIn( __METHOD__ );
 519                 $res = $db->select( 'revision',
 520                         array( 'rev_id', 'rev_len' ),
 521                         array( 'rev_id' => $revIds ),
 522                         __METHOD__ );
 523                 foreach ( $res as $row ) {
 524                         $revLens[$row->rev_id] = $row->rev_len;
 525                 }
 526                 wfProfileOut( __METHOD__ );
 527                 return $revLens;
 528         }
 529
 530         /**
 531          * Constructor
 532          *
 533          * @param object|array $row Either a database row or an array
 534          * @throws MWException
 535          * @access private
 536          */
 537         function __construct( $row ) {
 538                 if ( is_object( $row ) ) {
 539                         $this->mId = intval( $row->rev_id );
 540                         $this->mPage = intval( $row->rev_page );
 541                         $this->mTextId = intval( $row->rev_text_id );
 542                         $this->mComment = $row->rev_comment;
 543                         $this->mUser = intval( $row->rev_user );
 544                         $this->mMinorEdit = intval( $row->rev_minor_edit );
 545                         $this->mTimestamp = $row->rev_timestamp;
 546                         $this->mDeleted = intval( $row->rev_deleted );
 547
 548                         if ( !isset( $row->rev_parent_id ) ) {
 549                                 $this->mParentId = null;
 550                         } else {
 551                                 $this->mParentId = intval( $row->rev_parent_id );
 552                         }
 553
 554                         if ( !isset( $row->rev_len ) ) {
 555                                 $this->mSize = null;
 556                         } else {
 557                                 $this->mSize = intval( $row->rev_len );
 558                         }
 559
 560                         if ( !isset( $row->rev_sha1 ) ) {
 561                                 $this->mSha1 = null;
 562                         } else {
 563                                 $this->mSha1 = $row->rev_sha1;
 564                         }
 565
 566                         if ( isset( $row->page_latest ) ) {
 567                                 $this->mCurrent = ( $row->rev_id == $row->page_latest );
 568                                 $this->mTitle = Title::newFromRow( $row );
 569                         } else {
 570                                 $this->mCurrent = false;
 571                                 $this->mTitle = null;
 572                         }
 573
 574                         if ( !isset( $row->rev_content_model ) ) {
 575                                 $this->mContentModel = null; # determine on demand if needed
 576                         } else {
 577                                 $this->mContentModel = strval( $row->rev_content_model );
 578                         }
 579
 580                         if ( !isset( $row->rev_content_format ) ) {
 581                                 $this->mContentFormat = null; # determine on demand if needed
 582                         } else {
 583                                 $this->mContentFormat = strval( $row->rev_content_format );
 584                         }
 585
 586                         // Lazy extraction...
 587                         $this->mText = null;
 588                         if ( isset( $row->old_text ) ) {
 589                                 $this->mTextRow = $row;
 590                         } else {
 591                                 // 'text' table row entry will be lazy-loaded
 592                                 $this->mTextRow = null;
 593                         }
 594
 595                         // Use user_name for users and rev_user_text for IPs...
 596                         $this->mUserText = null; // lazy load if left null
 597                         if ( $this->mUser == 0 ) {
 598                                 $this->mUserText = $row->rev_user_text; // IP user
 599                         } elseif ( isset( $row->user_name ) ) {
 600                                 $this->mUserText = $row->user_name; // logged-in user
 601                         }
 602                         $this->mOrigUserText = $row->rev_user_text;
 603                 } elseif ( is_array( $row ) ) {
 604                         // Build a new revision to be saved...
 605                         global $wgUser; // ugh
 606
 607                         # if we have a content object, use it to set the model and type
 608                         if ( !empty( $row['content'] ) ) {
 609                                 // @todo when is that set? test with external store setup! check out insertOn() [dk]
 610                                 if ( !empty( $row['text_id'] ) ) {
 611                                         throw new MWException( "Text already stored in external store (id {$row['text_id']}), " .
 612                                                 "can't serialize content object" );
 613                                 }
 614
 615                                 $row['content_model'] = $row['content']->getModel();
 616                                 # note: mContentFormat is initializes later accordingly
 617                                 # note: content is serialized later in this method!
 618                                 # also set text to null?
 619                         }
 620
 621                         $this->mId = isset( $row['id'] ) ? intval( $row['id'] ) : null;
 622                         $this->mPage = isset( $row['page'] ) ? intval( $row['page'] ) : null;
 623                         $this->mTextId = isset( $row['text_id'] ) ? intval( $row['text_id'] ) : null;
 624                         $this->mUserText = isset( $row['user_text'] )
 625                                 ? strval( $row['user_text'] ) : $wgUser->getName();
 626                         $this->mUser = isset( $row['user'] ) ? intval( $row['user'] ) : $wgUser->getId();
 627                         $this->mMinorEdit = isset( $row['minor_edit'] ) ? intval( $row['minor_edit'] ) : 0;
 628                         $this->mTimestamp = isset( $row['timestamp'] )
 629                                 ? strval( $row['timestamp'] ) : wfTimestampNow();
 630                         $this->mDeleted = isset( $row['deleted'] ) ? intval( $row['deleted'] ) : 0;
 631                         $this->mSize = isset( $row['len'] ) ? intval( $row['len'] ) : null;
 632                         $this->mParentId = isset( $row['parent_id'] ) ? intval( $row['parent_id'] ) : null;
 633                         $this->mSha1 = isset( $row['sha1'] ) ? strval( $row['sha1'] ) : null;
 634
 635                         $this->mContentModel = isset( $row['content_model'] )
 636                                 ? strval( $row['content_model'] ) : null;
 637                         $this->mContentFormat = isset( $row['content_format'] )
 638                                 ? strval( $row['content_format'] ) : null;
 639
 640                         // Enforce spacing trimming on supplied text
 641                         $this->mComment = isset( $row['comment'] ) ? trim( strval( $row['comment'] ) ) : null;
 642                         $this->mText = isset( $row['text'] ) ? rtrim( strval( $row['text'] ) ) : null;
 643                         $this->mTextRow = null;
 644
 645                         $this->mTitle = isset( $row['title'] ) ? $row['title'] : null;
 646
 647                         // if we have a Content object, override mText and mContentModel
 648                         if ( !empty( $row['content'] ) ) {
 649                                 if ( !( $row['content'] instanceof Content ) ) {
 650                                         throw new MWException( '`content` field must contain a Content object.' );
 651                                 }
 652
 653                                 $handler = $this->getContentHandler();
 654                                 $this->mContent = $row['content'];
 655
 656                                 $this->mContentModel = $this->mContent->getModel();
 657                                 $this->mContentHandler = null;
 658
 659                                 $this->mText = $handler->serializeContent( $row['content'], $this->getContentFormat() );
 660                         } elseif ( $this->mText !== null ) {
 661                                 $handler = $this->getContentHandler();
 662                                 $this->mContent = $handler->unserializeContent( $this->mText );
 663                         }
 664
 665                         // If we have a Title object, make sure it is consistent with mPage.
 666                         if ( $this->mTitle && $this->mTitle->exists() ) {
 667                                 if ( $this->mPage === null ) {
 668                                         // if the page ID wasn't known, set it now
 669                                         $this->mPage = $this->mTitle->getArticleID();
 670                                 } elseif ( $this->mTitle->getArticleID() !== $this->mPage ) {
 671                                         // Got different page IDs. This may be legit (e.g. during undeletion),
 672                                         // but it seems worth mentioning it in the log.
 673                                         wfDebug( "Page ID " . $this->mPage . " mismatches the ID " .
 674                                                 $this->mTitle->getArticleID() . " provided by the Title object." );
 675                                 }
 676                         }
 677
 678                         $this->mCurrent = false;
 679
 680                         // If we still have no length, see it we have the text to figure it out
 681                         if ( !$this->mSize ) {
 682                                 if ( $this->mContent !== null ) {
 683                                         $this->mSize = $this->mContent->getSize();
 684                                 } else {
 685                                         #NOTE: this should never happen if we have either text or content object!
 686                                         $this->mSize = null;
 687                                 }
 688                         }
 689
 690                         // Same for sha1
 691                         if ( $this->mSha1 === null ) {
 692                                 $this->mSha1 = $this->mText === null ? null : self::base36Sha1( $this->mText );
 693                         }
 694
 695                         // force lazy init
 696                         $this->getContentModel();
 697                         $this->getContentFormat();
 698                 } else {
 699                         throw new MWException( 'Revision constructor passed invalid row format.' );
 700                 }
 701                 $this->mUnpatrolled = null;
 702         }
 703
 704         /**
 705          * Get revision ID
 706          *
 707          * @return int|null
 708          */
 709         public function getId() {
 710                 return $this->mId;
 711         }
 712
 713         /**
 714          * Set the revision ID
 715          *
 716          * @since 1.19
 717          * @param int $id
 718          */
 719         public function setId( $id ) {
 720                 $this->mId = $id;
 721         }
 722
 723         /**
 724          * Get text row ID
 725          *
 726          * @return int|null
 727          */
 728         public function getTextId() {
 729                 return $this->mTextId;
 730         }
 731
 732         /**
 733          * Get parent revision ID (the original previous page revision)
 734          *
 735          * @return int|null
 736          */
 737         public function getParentId() {
 738                 return $this->mParentId;
 739         }
 740
 741         /**
 742          * Returns the length of the text in this revision, or null if unknown.
 743          *
 744          * @return int|null
 745          */
 746         public function getSize() {
 747                 return $this->mSize;
 748         }
 749
 750         /**
 751          * Returns the base36 sha1 of the text in this revision, or null if unknown.
 752          *
 753          * @return string|null
 754          */
 755         public function getSha1() {
 756                 return $this->mSha1;
 757         }
 758
 759         /**
 760          * Returns the title of the page associated with this entry or null.
 761          *
 762          * Will do a query, when title is not set and id is given.
 763          *
 764          * @return Title|null
 765          */
 766         public function getTitle() {
 767                 if ( $this->mTitle !== null ) {
 768                         return $this->mTitle;
 769                 }
 770                 //rev_id is defined as NOT NULL, but this revision may not yet have been inserted.
 771                 if ( $this->mId !== null ) {
 772                         $dbr = wfGetDB( DB_SLAVE );
 773                         $row = $dbr->selectRow(
 774                                 array( 'page', 'revision' ),
 775                                 self::selectPageFields(),
 776                                 array( 'page_id=rev_page',
 777                                         'rev_id' => $this->mId ),
 778                                 __METHOD__ );
 779                         if ( $row ) {
 780                                 $this->mTitle = Title::newFromRow( $row );
 781                         }
 782                 }
 783
 784                 if ( !$this->mTitle && $this->mPage !== null && $this->mPage > 0 ) {
 785                         $this->mTitle = Title::newFromID( $this->mPage );
 786                 }
 787
 788                 return $this->mTitle;
 789         }
 790
 791         /**
 792          * Set the title of the revision
 793          *
 794          * @param Title $title
 795          */
 796         public function setTitle( $title ) {
 797                 $this->mTitle = $title;
 798         }
 799
 800         /**
 801          * Get the page ID
 802          *
 803          * @return int|null
 804          */
 805         public function getPage() {
 806                 return $this->mPage;
 807         }
 808
 809         /**
 810          * Fetch revision's user id if it's available to the specified audience.
 811          * If the specified audience does not have access to it, zero will be
 812          * returned.
 813          *
 814          * @param int $audience One of:
 815          *   Revision::FOR_PUBLIC       to be displayed to all users
 816          *   Revision::FOR_THIS_USER    to be displayed to the given user
 817          *   Revision::RAW              get the ID regardless of permissions
 818          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 819          *   to the $audience parameter
 820          * @return int
 821          */
 822         public function getUser( $audience = self::FOR_PUBLIC, User $user = null ) {
 823                 if ( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_USER ) ) {
 824                         return 0;
 825                 } elseif ( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_USER, $user ) ) {
 826                         return 0;
 827                 } else {
 828                         return $this->mUser;
 829                 }
 830         }
 831
 832         /**
 833          * Fetch revision's user id without regard for the current user's permissions
 834          *
 835          * @return string
 836          */
 837         public function getRawUser() {
 838                 return $this->mUser;
 839         }
 840
 841         /**
 842          * Fetch revision's username if it's available to the specified audience.
 843          * If the specified audience does not have access to the username, an
 844          * empty string will be returned.
 845          *
 846          * @param int $audience One of:
 847          *   Revision::FOR_PUBLIC       to be displayed to all users
 848          *   Revision::FOR_THIS_USER    to be displayed to the given user
 849          *   Revision::RAW              get the text regardless of permissions
 850          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 851          *   to the $audience parameter
 852          * @return string
 853          */
 854         public function getUserText( $audience = self::FOR_PUBLIC, User $user = null ) {
 855                 if ( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_USER ) ) {
 856                         return '';
 857                 } elseif ( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_USER, $user ) ) {
 858                         return '';
 859                 } else {
 860                         return $this->getRawUserText();
 861                 }
 862         }
 863
 864         /**
 865          * Fetch revision's username without regard for view restrictions
 866          *
 867          * @return string
 868          */
 869         public function getRawUserText() {
 870                 if ( $this->mUserText === null ) {
 871                         $this->mUserText = User::whoIs( $this->mUser ); // load on demand
 872                         if ( $this->mUserText === false ) {
 873                                 # This shouldn't happen, but it can if the wiki was recovered
 874                                 # via importing revs and there is no user table entry yet.
 875                                 $this->mUserText = $this->mOrigUserText;
 876                         }
 877                 }
 878                 return $this->mUserText;
 879         }
 880
 881         /**
 882          * Fetch revision comment if it's available to the specified audience.
 883          * If the specified audience does not have access to the comment, an
 884          * empty string will be returned.
 885          *
 886          * @param int $audience One of:
 887          *   Revision::FOR_PUBLIC       to be displayed to all users
 888          *   Revision::FOR_THIS_USER    to be displayed to the given user
 889          *   Revision::RAW              get the text regardless of permissions
 890          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 891          *   to the $audience parameter
 892          * @return string
 893          */
 894         function getComment( $audience = self::FOR_PUBLIC, User $user = null ) {
 895                 if ( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_COMMENT ) ) {
 896                         return '';
 897                 } elseif ( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_COMMENT, $user ) ) {
 898                         return '';
 899                 } else {
 900                         return $this->mComment;
 901                 }
 902         }
 903
 904         /**
 905          * Fetch revision comment without regard for the current user's permissions
 906          *
 907          * @return string
 908          */
 909         public function getRawComment() {
 910                 return $this->mComment;
 911         }
 912
 913         /**
 914          * @return bool
 915          */
 916         public function isMinor() {
 917                 return (bool)$this->mMinorEdit;
 918         }
 919
 920         /**
 921          * @return int Rcid of the unpatrolled row, zero if there isn't one
 922          */
 923         public function isUnpatrolled() {
 924                 if ( $this->mUnpatrolled !== null ) {
 925                         return $this->mUnpatrolled;
 926                 }
 927                 $rc = $this->getRecentChange();
 928                 if ( $rc && $rc->getAttribute( 'rc_patrolled' ) == 0 ) {
 929                         $this->mUnpatrolled = $rc->getAttribute( 'rc_id' );
 930                 } else {
 931                         $this->mUnpatrolled = 0;
 932                 }
 933                 return $this->mUnpatrolled;
 934         }
 935
 936         /**
 937          * Get the RC object belonging to the current revision, if there's one
 938          *
 939          * @since 1.22
 940          * @return RecentChange|null
 941          */
 942         public function getRecentChange() {
 943                 $dbr = wfGetDB( DB_SLAVE );
 944                 return RecentChange::newFromConds(
 945                         array(
 946                                 'rc_user_text' => $this->getRawUserText(),
 947                                 'rc_timestamp' => $dbr->timestamp( $this->getTimestamp() ),
 948                                 'rc_this_oldid' => $this->getId()
 949                         ),
 950                         __METHOD__
 951                 );
 952         }
 953
 954         /**
 955          * @param int $field One of DELETED_* bitfield constants
 956          *
 957          * @return bool
 958          */
 959         public function isDeleted( $field ) {
 960                 return ( $this->mDeleted & $field ) == $field;
 961         }
 962
 963         /**
 964          * Get the deletion bitfield of the revision
 965          *
 966          * @return int
 967          */
 968         public function getVisibility() {
 969                 return (int)$this->mDeleted;
 970         }
 971
 972         /**
 973          * Fetch revision text if it's available to the specified audience.
 974          * If the specified audience does not have the ability to view this
 975          * revision, an empty string will be returned.
 976          *
 977          * @param int $audience One of:
 978          *   Revision::FOR_PUBLIC       to be displayed to all users
 979          *   Revision::FOR_THIS_USER    to be displayed to the given user
 980          *   Revision::RAW              get the text regardless of permissions
 981          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 982          *   to the $audience parameter
 983          *
 984          * @deprecated since 1.21, use getContent() instead
 985          * @todo Replace usage in core
 986          * @return string
 987          */
 988         public function getText( $audience = self::FOR_PUBLIC, User $user = null ) {
 989                 ContentHandler::deprecated( __METHOD__, '1.21' );
 990
 991                 $content = $this->getContent( $audience, $user );
 992                 return ContentHandler::getContentText( $content ); # returns the raw content text, if applicable
 993         }
 994
 995         /**
 996          * Fetch revision content if it's available to the specified audience.
 997          * If the specified audience does not have the ability to view this
 998          * revision, null will be returned.
 999          *
1000          * @param int $audience One of:
1001          *   Revision::FOR_PUBLIC       to be displayed to all users
1002          *   Revision::FOR_THIS_USER    to be displayed to $wgUser
1003          *   Revision::RAW              get the text regardless of permissions
1004          * @param User $user User object to check for, only if FOR_THIS_USER is passed
1005          *   to the $audience parameter
1006          * @since 1.21
1007          * @return Content|null
1008          */
1009         public function getContent( $audience = self::FOR_PUBLIC, User $user = null ) {
1010                 if ( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_TEXT ) ) {
1011                         return null;
1012                 } elseif ( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_TEXT, $user ) ) {
1013                         return null;
1014                 } else {
1015                         return $this->getContentInternal();
1016                 }
1017         }
1018
1019         /**
1020          * Fetch revision text without regard for view restrictions
1021          *
1022          * @return string
1023          *
1024          * @deprecated since 1.21. Instead, use Revision::getContent( Revision::RAW )
1025          *                         or Revision::getSerializedData() as appropriate.
1026          */
1027         public function getRawText() {
1028                 ContentHandler::deprecated( __METHOD__, "1.21" );
1029                 return $this->getText( self::RAW );
1030         }
1031
1032         /**
1033          * Fetch original serialized data without regard for view restrictions
1034          *
1035          * @since 1.21
1036          * @return string
1037          */
1038         public function getSerializedData() {
1039                 if ( $this->mText === null ) {
1040                         $this->mText = $this->loadText();
1041                 }
1042
1043                 return $this->mText;
1044         }
1045
1046         /**
1047          * Gets the content object for the revision (or null on failure).
1048          *
1049          * Note that for mutable Content objects, each call to this method will return a
1050          * fresh clone.
1051          *
1052          * @since 1.21
1053          * @return Content|null The Revision's content, or null on failure.
1054          */
1055         protected function getContentInternal() {
1056                 if ( $this->mContent === null ) {
1057                         // Revision is immutable. Load on demand:
1058                         if ( $this->mText === null ) {
1059                                 $this->mText = $this->loadText();
1060                         }
1061
1062                         if ( $this->mText !== null && $this->mText !== false ) {
1063                                 // Unserialize content
1064                                 $handler = $this->getContentHandler();
1065                                 $format = $this->getContentFormat();
1066
1067                                 $this->mContent = $handler->unserializeContent( $this->mText, $format );
1068                         } else {
1069                                 $this->mContent = false; // negative caching!
1070                         }
1071                 }
1072
1073                 // NOTE: copy() will return $this for immutable content objects
1074                 return $this->mContent ? $this->mContent->copy() : null;
1075         }
1076
1077         /**
1078          * Returns the content model for this revision.
1079          *
1080          * If no content model was stored in the database, $this->getTitle()->getContentModel() is
1081          * used to determine the content model to use. If no title is know, CONTENT_MODEL_WIKITEXT
1082          * is used as a last resort.
1083          *
1084          * @return string The content model id associated with this revision,
1085          *     see the CONTENT_MODEL_XXX constants.
1086          **/
1087         public function getContentModel() {
1088                 if ( !$this->mContentModel ) {
1089                         $title = $this->getTitle();
1090                         $this->mContentModel = ( $title ? $title->getContentModel() : CONTENT_MODEL_WIKITEXT );
1091
1092                         assert( !empty( $this->mContentModel ) );
1093                 }
1094
1095                 return $this->mContentModel;
1096         }
1097
1098         /**
1099          * Returns the content format for this revision.
1100          *
1101          * If no content format was stored in the database, the default format for this
1102          * revision's content model is returned.
1103          *
1104          * @return string The content format id associated with this revision,
1105          *     see the CONTENT_FORMAT_XXX constants.
1106          **/
1107         public function getContentFormat() {
1108                 if ( !$this->mContentFormat ) {
1109                         $handler = $this->getContentHandler();
1110                         $this->mContentFormat = $handler->getDefaultFormat();
1111
1112                         assert( !empty( $this->mContentFormat ) );
1113                 }
1114
1115                 return $this->mContentFormat;
1116         }
1117
1118         /**
1119          * Returns the content handler appropriate for this revision's content model.
1120          *
1121          * @throws MWException
1122          * @return ContentHandler
1123          */
1124         public function getContentHandler() {
1125                 if ( !$this->mContentHandler ) {
1126                         $model = $this->getContentModel();
1127                         $this->mContentHandler = ContentHandler::getForModelID( $model );
1128
1129                         $format = $this->getContentFormat();
1130
1131                         if ( !$this->mContentHandler->isSupportedFormat( $format ) ) {
1132                                 throw new MWException( "Oops, the content format $format is not supported for "
1133                                         . "this content model, $model" );
1134                         }
1135                 }
1136
1137                 return $this->mContentHandler;
1138         }
1139
1140         /**
1141          * @return string
1142          */
1143         public function getTimestamp() {
1144                 return wfTimestamp( TS_MW, $this->mTimestamp );
1145         }
1146
1147         /**
1148          * @return bool
1149          */
1150         public function isCurrent() {
1151                 return $this->mCurrent;
1152         }
1153
1154         /**
1155          * Get previous revision for this title
1156          *
1157          * @return Revision|null
1158          */
1159         public function getPrevious() {
1160                 if ( $this->getTitle() ) {
1161                         $prev = $this->getTitle()->getPreviousRevisionID( $this->getId() );
1162                         if ( $prev ) {
1163                                 return self::newFromTitle( $this->getTitle(), $prev );
1164                         }
1165                 }
1166                 return null;
1167         }
1168
1169         /**
1170          * Get next revision for this title
1171          *
1172          * @return Revision|null
1173          */
1174         public function getNext() {
1175                 if ( $this->getTitle() ) {
1176                         $next = $this->getTitle()->getNextRevisionID( $this->getId() );
1177                         if ( $next ) {
1178                                 return self::newFromTitle( $this->getTitle(), $next );
1179                         }
1180                 }
1181                 return null;
1182         }
1183
1184         /**
1185          * Get previous revision Id for this page_id
1186          * This is used to populate rev_parent_id on save
1187          *
1188          * @param DatabaseBase $db
1189          * @return int
1190          */
1191         private function getPreviousRevisionId( $db ) {
1192                 if ( $this->mPage === null ) {
1193                         return 0;
1194                 }
1195                 # Use page_latest if ID is not given
1196                 if ( !$this->mId ) {
1197                         $prevId = $db->selectField( 'page', 'page_latest',
1198                                 array( 'page_id' => $this->mPage ),
1199                                 __METHOD__ );
1200                 } else {
1201                         $prevId = $db->selectField( 'revision', 'rev_id',
1202                                 array( 'rev_page' => $this->mPage, 'rev_id < ' . $this->mId ),
1203                                 __METHOD__,
1204                                 array( 'ORDER BY' => 'rev_id DESC' ) );
1205                 }
1206                 return intval( $prevId );
1207         }
1208
1209         /**
1210          * Get revision text associated with an old or archive row
1211          * $row is usually an object from wfFetchRow(), both the flags and the text
1212          * field must be included.
1213          *
1214          * @param stdClass $row The text data
1215          * @param string $prefix Table prefix (default 'old_')
1216          * @param string|bool $wiki The name of the wiki to load the revision text from
1217          *   (same as the the wiki $row was loaded from) or false to indicate the local
1218          *   wiki (this is the default). Otherwise, it must be a symbolic wiki database
1219          *   identifier as understood by the LoadBalancer class.
1220          * @return string Text the text requested or false on failure
1221          */
1222         public static function getRevisionText( $row, $prefix = 'old_', $wiki = false ) {
1223                 wfProfileIn( __METHOD__ );
1224
1225                 # Get data
1226                 $textField = $prefix . 'text';
1227                 $flagsField = $prefix . 'flags';
1228
1229                 if ( isset( $row->$flagsField ) ) {
1230                         $flags = explode( ',', $row->$flagsField );
1231                 } else {
1232                         $flags = array();
1233                 }
1234
1235                 if ( isset( $row->$textField ) ) {
1236                         $text = $row->$textField;
1237                 } else {
1238                         wfProfileOut( __METHOD__ );
1239                         return false;
1240                 }
1241
1242                 # Use external methods for external objects, text in table is URL-only then
1243                 if ( in_array( 'external', $flags ) ) {
1244                         $url = $text;
1245                         $parts = explode( '://', $url, 2 );
1246                         if ( count( $parts ) == 1 || $parts[1] == '' ) {
1247                                 wfProfileOut( __METHOD__ );
1248                                 return false;
1249                         }
1250                         $text = ExternalStore::fetchFromURL( $url, array( 'wiki' => $wiki ) );
1251                 }
1252
1253                 // If the text was fetched without an error, convert it
1254                 if ( $text !== false ) {
1255                         $text = self::decompressRevisionText( $text, $flags );
1256                 }
1257                 wfProfileOut( __METHOD__ );
1258                 return $text;
1259         }
1260
1261         /**
1262          * If $wgCompressRevisions is enabled, we will compress data.
1263          * The input string is modified in place.
1264          * Return value is the flags field: contains 'gzip' if the
1265          * data is compressed, and 'utf-8' if we're saving in UTF-8
1266          * mode.
1267          *
1268          * @param mixed $text Reference to a text
1269          * @return string
1270          */
1271         public static function compressRevisionText( &$text ) {
1272                 global $wgCompressRevisions;
1273                 $flags = array();
1274
1275                 # Revisions not marked this way will be converted
1276                 # on load if $wgLegacyCharset is set in the future.
1277                 $flags[] = 'utf-8';
1278
1279                 if ( $wgCompressRevisions ) {
1280                         if ( function_exists( 'gzdeflate' ) ) {
1281                                 $text = gzdeflate( $text );
1282                                 $flags[] = 'gzip';
1283                         } else {
1284                                 wfDebug( __METHOD__ . " -- no zlib support, not compressing\n" );
1285                         }
1286                 }
1287                 return implode( ',', $flags );
1288         }
1289
1290         /**
1291          * Re-converts revision text according to it's flags.
1292          *
1293          * @param mixed $text Reference to a text
1294          * @param array $flags Compression flags
1295          * @return string|bool Decompressed text, or false on failure
1296          */
1297         public static function decompressRevisionText( $text, $flags ) {
1298                 if ( in_array( 'gzip', $flags ) ) {
1299                         # Deal with optional compression of archived pages.
1300                         # This can be done periodically via maintenance/compressOld.php, and
1301                         # as pages are saved if $wgCompressRevisions is set.
1302                         $text = gzinflate( $text );
1303                 }
1304
1305                 if ( in_array( 'object', $flags ) ) {
1306                         # Generic compressed storage
1307                         $obj = unserialize( $text );
1308                         if ( !is_object( $obj ) ) {
1309                                 // Invalid object
1310                                 return false;
1311                         }
1312                         $text = $obj->getText();
1313                 }
1314
1315                 global $wgLegacyEncoding;
1316                 if ( $text !== false && $wgLegacyEncoding
1317                         && !in_array( 'utf-8', $flags ) && !in_array( 'utf8', $flags )
1318                 ) {
1319                         # Old revisions kept around in a legacy encoding?
1320                         # Upconvert on demand.
1321                         # ("utf8" checked for compatibility with some broken
1322                         #  conversion scripts 2008-12-30)
1323                         global $wgContLang;
1324                         $text = $wgContLang->iconv( $wgLegacyEncoding, 'UTF-8', $text );
1325                 }
1326
1327                 return $text;
1328         }
1329
1330         /**
1331          * Insert a new revision into the database, returning the new revision ID
1332          * number on success and dies horribly on failure.
1333          *
1334          * @param DatabaseBase $dbw (master connection)
1335          * @throws MWException
1336          * @return int
1337          */
1338         public function insertOn( $dbw ) {
1339                 global $wgDefaultExternalStore, $wgContentHandlerUseDB;
1340
1341                 wfProfileIn( __METHOD__ );
1342
1343                 $this->checkContentModel();
1344
1345                 $data = $this->mText;
1346                 $flags = self::compressRevisionText( $data );
1347
1348                 # Write to external storage if required
1349                 if ( $wgDefaultExternalStore ) {
1350                         // Store and get the URL
1351                         $data = ExternalStore::insertToDefault( $data );
1352                         if ( !$data ) {
1353                                 wfProfileOut( __METHOD__ );
1354                                 throw new MWException( "Unable to store text to external storage" );
1355                         }
1356                         if ( $flags ) {
1357                                 $flags .= ',';
1358                         }
1359                         $flags .= 'external';
1360                 }
1361
1362                 # Record the text (or external storage URL) to the text table
1363                 if ( $this->mTextId === null ) {
1364                         $old_id = $dbw->nextSequenceValue( 'text_old_id_seq' );
1365                         $dbw->insert( 'text',
1366                                 array(
1367                                         'old_id' => $old_id,
1368                                         'old_text' => $data,
1369                                         'old_flags' => $flags,
1370                                 ), __METHOD__
1371                         );
1372                         $this->mTextId = $dbw->insertId();
1373                 }
1374
1375                 if ( $this->mComment === null ) {
1376                         $this->mComment = "";
1377                 }
1378
1379                 # Record the edit in revisions
1380                 $rev_id = $this->mId !== null
1381                         ? $this->mId
1382                         : $dbw->nextSequenceValue( 'revision_rev_id_seq' );
1383                 $row = array(
1384                         'rev_id'         => $rev_id,
1385                         'rev_page'       => $this->mPage,
1386                         'rev_text_id'    => $this->mTextId,
1387                         'rev_comment'    => $this->mComment,
1388                         'rev_minor_edit' => $this->mMinorEdit ? 1 : 0,
1389                         'rev_user'       => $this->mUser,
1390                         'rev_user_text'  => $this->mUserText,
1391                         'rev_timestamp'  => $dbw->timestamp( $this->mTimestamp ),
1392                         'rev_deleted'    => $this->mDeleted,
1393                         'rev_len'        => $this->mSize,
1394                         'rev_parent_id'  => $this->mParentId === null
1395                                 ? $this->getPreviousRevisionId( $dbw )
1396                                 : $this->mParentId,
1397                         'rev_sha1'       => $this->mSha1 === null
1398                                 ? Revision::base36Sha1( $this->mText )
1399                                 : $this->mSha1,
1400                 );
1401
1402                 if ( $wgContentHandlerUseDB ) {
1403                         //NOTE: Store null for the default model and format, to save space.
1404                         //XXX: Makes the DB sensitive to changed defaults.
1405                         // Make this behavior optional? Only in miser mode?
1406
1407                         $model = $this->getContentModel();
1408                         $format = $this->getContentFormat();
1409
1410                         $title = $this->getTitle();
1411
1412                         if ( $title === null ) {
1413                                 wfProfileOut( __METHOD__ );
1414                                 throw new MWException( "Insufficient information to determine the title of the "
1415                                         . "revision's page!" );
1416                         }
1417
1418                         $defaultModel = ContentHandler::getDefaultModelFor( $title );
1419                         $defaultFormat = ContentHandler::getForModelID( $defaultModel )->getDefaultFormat();
1420
1421                         $row['rev_content_model'] = ( $model === $defaultModel ) ? null : $model;
1422                         $row['rev_content_format'] = ( $format === $defaultFormat ) ? null : $format;
1423                 }
1424
1425                 $dbw->insert( 'revision', $row, __METHOD__ );
1426
1427                 $this->mId = $rev_id !== null ? $rev_id : $dbw->insertId();
1428
1429                 wfRunHooks( 'RevisionInsertComplete', array( &$this, $data, $flags ) );
1430
1431                 wfProfileOut( __METHOD__ );
1432                 return $this->mId;
1433         }
1434
1435         protected function checkContentModel() {
1436                 global $wgContentHandlerUseDB;
1437
1438                 $title = $this->getTitle(); //note: may return null for revisions that have not yet been inserted.
1439
1440                 $model = $this->getContentModel();
1441                 $format = $this->getContentFormat();
1442                 $handler = $this->getContentHandler();
1443
1444                 if ( !$handler->isSupportedFormat( $format ) ) {
1445                         $t = $title->getPrefixedDBkey();
1446
1447                         throw new MWException( "Can't use format $format with content model $model on $t" );
1448                 }
1449
1450                 if ( !$wgContentHandlerUseDB && $title ) {
1451                         // if $wgContentHandlerUseDB is not set,
1452                         // all revisions must use the default content model and format.
1453
1454                         $defaultModel = ContentHandler::getDefaultModelFor( $title );
1455                         $defaultHandler = ContentHandler::getForModelID( $defaultModel );
1456                         $defaultFormat = $defaultHandler->getDefaultFormat();
1457
1458                         if ( $this->getContentModel() != $defaultModel ) {
1459                                 $t = $title->getPrefixedDBkey();
1460
1461                                 throw new MWException( "Can't save non-default content model with "
1462                                         . "\$wgContentHandlerUseDB disabled: model is $model, "
1463                                         . "default for $t is $defaultModel" );
1464                         }
1465
1466                         if ( $this->getContentFormat() != $defaultFormat ) {
1467                                 $t = $title->getPrefixedDBkey();
1468
1469                                 throw new MWException( "Can't use non-default content format with "
1470                                         . "\$wgContentHandlerUseDB disabled: format is $format, "
1471                                         . "default for $t is $defaultFormat" );
1472                         }
1473                 }
1474
1475                 $content = $this->getContent( Revision::RAW );
1476
1477                 if ( !$content || !$content->isValid() ) {
1478                         $t = $title->getPrefixedDBkey();
1479
1480                         throw new MWException( "Content of $t is not valid! Content model is $model" );
1481                 }
1482         }
1483
1484         /**
1485          * Get the base 36 SHA-1 value for a string of text
1486          * @param string $text
1487          * @return string
1488          */
1489         public static function base36Sha1( $text ) {
1490                 return wfBaseConvert( sha1( $text ), 16, 36, 31 );
1491         }
1492
1493         /**
1494          * Lazy-load the revision's text.
1495          * Currently hardcoded to the 'text' table storage engine.
1496          *
1497          * @return string|bool The revision's text, or false on failure
1498          */
1499         protected function loadText() {
1500                 wfProfileIn( __METHOD__ );
1501
1502                 // Caching may be beneficial for massive use of external storage
1503                 global $wgRevisionCacheExpiry, $wgMemc;
1504                 $textId = $this->getTextId();
1505                 $key = wfMemcKey( 'revisiontext', 'textid', $textId );
1506                 if ( $wgRevisionCacheExpiry ) {
1507                         $text = $wgMemc->get( $key );
1508                         if ( is_string( $text ) ) {
1509                                 wfDebug( __METHOD__ . ": got id $textId from cache\n" );
1510                                 wfProfileOut( __METHOD__ );
1511                                 return $text;
1512                         }
1513                 }
1514
1515                 // If we kept data for lazy extraction, use it now...
1516                 if ( $this->mTextRow !== null ) {
1517                         $row = $this->mTextRow;
1518                         $this->mTextRow = null;
1519                 } else {
1520                         $row = null;
1521                 }
1522
1523                 if ( !$row ) {
1524                         // Text data is immutable; check slaves first.
1525                         $dbr = wfGetDB( DB_SLAVE );
1526                         $row = $dbr->selectRow( 'text',
1527                                 array( 'old_text', 'old_flags' ),
1528                                 array( 'old_id' => $textId ),
1529                                 __METHOD__ );
1530                 }
1531
1532                 // Fallback to the master in case of slave lag. Also use FOR UPDATE if it was
1533                 // used to fetch this revision to avoid missing the row due to REPEATABLE-READ.
1534                 $forUpdate = ( $this->mQueryFlags & self::READ_LOCKING == self::READ_LOCKING );
1535                 if ( !$row && ( $forUpdate || wfGetLB()->getServerCount() > 1 ) ) {
1536                         $dbw = wfGetDB( DB_MASTER );
1537                         $row = $dbw->selectRow( 'text',
1538                                 array( 'old_text', 'old_flags' ),
1539                                 array( 'old_id' => $textId ),
1540                                 __METHOD__,
1541                                 $forUpdate ? array( 'FOR UPDATE' ) : array() );
1542                 }
1543
1544                 if ( !$row ) {
1545                         wfDebugLog( 'Revision', "No text row with ID '$textId' (revision {$this->getId()})." );
1546                 }
1547
1548                 $text = self::getRevisionText( $row );
1549                 if ( $row && $text === false ) {
1550                         wfDebugLog( 'Revision', "No blob for text row '$textId' (revision {$this->getId()})." );
1551                 }
1552
1553                 # No negative caching -- negative hits on text rows may be due to corrupted slave servers
1554                 if ( $wgRevisionCacheExpiry && $text !== false ) {
1555                         $wgMemc->set( $key, $text, $wgRevisionCacheExpiry );
1556                 }
1557
1558                 wfProfileOut( __METHOD__ );
1559
1560                 return $text;
1561         }
1562
1563         /**
1564          * Create a new null-revision for insertion into a page's
1565          * history. This will not re-save the text, but simply refer
1566          * to the text from the previous version.
1567          *
1568          * Such revisions can for instance identify page rename
1569          * operations and other such meta-modifications.
1570          *
1571          * @param DatabaseBase $dbw
1572          * @param int $pageId ID number of the page to read from
1573          * @param string $summary Revision's summary
1574          * @param bool $minor Whether the revision should be considered as minor
1575          * @param User|null $user User object to use or null for $wgUser
1576          * @return Revision|null Revision or null on error
1577          */
1578         public static function newNullRevision( $dbw, $pageId, $summary, $minor, $user = null ) {
1579                 global $wgContentHandlerUseDB;
1580
1581                 wfProfileIn( __METHOD__ );
1582
1583                 $fields = array( 'page_latest', 'page_namespace', 'page_title',
1584                                                 'rev_text_id', 'rev_len', 'rev_sha1' );
1585
1586                 if ( $wgContentHandlerUseDB ) {
1587                         $fields[] = 'rev_content_model';
1588                         $fields[] = 'rev_content_format';
1589                 }
1590
1591                 $current = $dbw->selectRow(
1592                         array( 'page', 'revision' ),
1593                         $fields,
1594                         array(
1595                                 'page_id' => $pageId,
1596                                 'page_latest=rev_id',
1597                                 ),
1598                         __METHOD__ );
1599
1600                 if ( $current ) {
1601                         if ( !$user ) {
1602                                 global $wgUser;
1603                                 $user = $wgUser;
1604                         }
1605
1606                         $row = array(
1607                                 'page'       => $pageId,
1608                                 'user_text'  => $user->getName(),
1609                                 'user'       => $user->getId(),
1610                                 'comment'    => $summary,
1611                                 'minor_edit' => $minor,
1612                                 'text_id'    => $current->rev_text_id,
1613                                 'parent_id'  => $current->page_latest,
1614                                 'len'        => $current->rev_len,
1615                                 'sha1'       => $current->rev_sha1
1616                         );
1617
1618                         if ( $wgContentHandlerUseDB ) {
1619                                 $row['content_model'] = $current->rev_content_model;
1620                                 $row['content_format'] = $current->rev_content_format;
1621                         }
1622
1623                         $revision = new Revision( $row );
1624                         $revision->setTitle( Title::makeTitle( $current->page_namespace, $current->page_title ) );
1625                 } else {
1626                         $revision = null;
1627                 }
1628
1629                 wfProfileOut( __METHOD__ );
1630                 return $revision;
1631         }
1632
1633         /**
1634          * Determine if the current user is allowed to view a particular
1635          * field of this revision, if it's marked as deleted.
1636          *
1637          * @param int $field One of self::DELETED_TEXT,
1638          *                              self::DELETED_COMMENT,
1639          *                              self::DELETED_USER
1640          * @param User|null $user User object to check, or null to use $wgUser
1641          * @return bool
1642          */
1643         public function userCan( $field, User $user = null ) {
1644                 return self::userCanBitfield( $this->mDeleted, $field, $user );
1645         }
1646
1647         /**
1648          * Determine if the current user is allowed to view a particular
1649          * field of this revision, if it's marked as deleted. This is used
1650          * by various classes to avoid duplication.
1651          *
1652          * @param int $bitfield Current field
1653          * @param int $field One of self::DELETED_TEXT = File::DELETED_FILE,
1654          *                               self::DELETED_COMMENT = File::DELETED_COMMENT,
1655          *                               self::DELETED_USER = File::DELETED_USER
1656          * @param User|null $user User object to check, or null to use $wgUser
1657          * @param Title|null $title A Title object to check for per-page restrictions on,
1658          *                          instead of just plain userrights
1659          * @return bool
1660          */
1661         public static function userCanBitfield( $bitfield, $field, User $user = null,
1662                 Title $title = null
1663         ) {
1664                 if ( $bitfield & $field ) { // aspect is deleted
1665                         if ( $user === null ) {
1666                                 global $wgUser;
1667                                 $user = $wgUser;
1668                         }
1669                         if ( $bitfield & self::DELETED_RESTRICTED ) {
1670                                 $permissions = array( 'suppressrevision', 'viewsuppressed' );
1671                         } elseif ( $field & self::DELETED_TEXT ) {
1672                                 $permissions = array( 'deletedtext' );
1673                         } else {
1674                                 $permissions = array( 'deletedhistory' );
1675                         }
1676                         $permissionlist = implode( ', ', $permissions );
1677                         if ( $title === null ) {
1678                                 wfDebug( "Checking for $permissionlist due to $field match on $bitfield\n" );
1679                                 return call_user_func_array( array( $user, 'isAllowedAny' ), $permissions );
1680                         } else {
1681                                 $text = $title->getPrefixedText();
1682                                 wfDebug( "Checking for $permissionlist on $text due to $field match on $bitfield\n" );
1683                                 foreach ( $permissions as $perm ) {
1684                                         if ( $title->userCan( $perm, $user ) ) {
1685                                                 return true;
1686                                         }
1687                                 }
1688                                 return false;
1689                         }
1690                 } else {
1691                         return true;
1692                 }
1693         }
1694
1695         /**
1696          * Get rev_timestamp from rev_id, without loading the rest of the row
1697          *
1698          * @param Title $title
1699          * @param int $id
1700          * @return string
1701          */
1702         static function getTimestampFromId( $title, $id ) {
1703                 $dbr = wfGetDB( DB_SLAVE );
1704                 // Casting fix for databases that can't take '' for rev_id
1705                 if ( $id == '' ) {
1706                         $id = 0;
1707                 }
1708                 $conds = array( 'rev_id' => $id );
1709                 $conds['rev_page'] = $title->getArticleID();
1710                 $timestamp = $dbr->selectField( 'revision', 'rev_timestamp', $conds, __METHOD__ );
1711                 if ( $timestamp === false && wfGetLB()->getServerCount() > 1 ) {
1712                         # Not in slave, try master
1713                         $dbw = wfGetDB( DB_MASTER );
1714                         $timestamp = $dbw->selectField( 'revision', 'rev_timestamp', $conds, __METHOD__ );
1715                 }
1716                 return wfTimestamp( TS_MW, $timestamp );
1717         }
1718
1719         /**
1720          * Get count of revisions per page...not very efficient
1721          *
1722          * @param DatabaseBase $db
1723          * @param int $id Page id
1724          * @return int
1725          */
1726         static function countByPageId( $db, $id ) {
1727                 $row = $db->selectRow( 'revision', array( 'revCount' => 'COUNT(*)' ),
1728                         array( 'rev_page' => $id ), __METHOD__ );
1729                 if ( $row ) {
1730                         return $row->revCount;
1731                 }
1732                 return 0;
1733         }
1734
1735         /**
1736          * Get count of revisions per page...not very efficient
1737          *
1738          * @param DatabaseBase $db
1739          * @param Title $title
1740          * @return int
1741          */
1742         static function countByTitle( $db, $title ) {
1743                 $id = $title->getArticleID();
1744                 if ( $id ) {
1745                         return self::countByPageId( $db, $id );
1746                 }
1747                 return 0;
1748         }
1749
1750         /**
1751          * Check if no edits were made by other users since
1752          * the time a user started editing the page. Limit to
1753          * 50 revisions for the sake of performance.
1754          *
1755          * @since 1.20
1756          * @deprecated since 1.24
1757          *
1758          * @param DatabaseBase|int $db The Database to perform the check on. May be given as a
1759          *        Database object or a database identifier usable with wfGetDB.
1760          * @param int $pageId The ID of the page in question
1761          * @param int $userId The ID of the user in question
1762          * @param string $since Look at edits since this time
1763          *
1764          * @return bool True if the given user was the only one to edit since the given timestamp
1765          */
1766         public static function userWasLastToEdit( $db, $pageId, $userId, $since ) {
1767                 if ( !$userId ) {
1768                         return false;
1769                 }
1770
1771                 if ( is_int( $db ) ) {
1772                         $db = wfGetDB( $db );
1773                 }
1774
1775                 $res = $db->select( 'revision',
1776                         'rev_user',
1777                         array(
1778                                 'rev_page' => $pageId,
1779                                 'rev_timestamp > ' . $db->addQuotes( $db->timestamp( $since ) )
1780                         ),
1781                         __METHOD__,
1782                         array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 50 ) );
1783                 foreach ( $res as $row ) {
1784                         if ( $row->rev_user != $userId ) {
1785                                 return false;
1786                         }
1787                 }
1788                 return true;
1789         }
1790 }