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, $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                         return self::newFromConds( $conds, $flags );
 152                 } else {
 153                         // Use a join to get the latest revision
 154                         $conds[] = 'rev_id = page_latest';
 155                         $db = wfGetDB( ( $flags & self::READ_LATEST ) ? DB_MASTER : DB_SLAVE );
 156                         return self::loadFromConds( $db, $conds, $flags );
 157                 }
 158         }
 159
 160         /**
 161          * Make a fake revision object from an archive table row. This is queried
 162          * for permissions or even inserted (as in Special:Undelete)
 163          * @todo FIXME: Should be a subclass for RevisionDelete. [TS]
 164          *
 165          * @param object $row
 166          * @param array $overrides
 167          *
 168          * @throws MWException
 169          * @return Revision
 170          */
 171         public static function newFromArchiveRow( $row, $overrides = array() ) {
 172                 global $wgContentHandlerUseDB;
 173
 174                 $attribs = $overrides + array(
 175                         'page'       => isset( $row->ar_page_id ) ? $row->ar_page_id : null,
 176                         'id'         => isset( $row->ar_rev_id ) ? $row->ar_rev_id : null,
 177                         'comment'    => $row->ar_comment,
 178                         'user'       => $row->ar_user,
 179                         'user_text'  => $row->ar_user_text,
 180                         'timestamp'  => $row->ar_timestamp,
 181                         'minor_edit' => $row->ar_minor_edit,
 182                         'text_id'    => isset( $row->ar_text_id ) ? $row->ar_text_id : null,
 183                         'deleted'    => $row->ar_deleted,
 184                         'len'        => $row->ar_len,
 185                         'sha1'       => isset( $row->ar_sha1 ) ? $row->ar_sha1 : null,
 186                         'content_model'   => isset( $row->ar_content_model ) ? $row->ar_content_model : null,
 187                         'content_format'  => isset( $row->ar_content_format ) ? $row->ar_content_format : null,
 188                 );
 189
 190                 if ( !$wgContentHandlerUseDB ) {
 191                         unset( $attribs['content_model'] );
 192                         unset( $attribs['content_format'] );
 193                 }
 194
 195                 if ( !isset( $attribs['title'] )
 196                         && isset( $row->ar_namespace )
 197                         && isset( $row->ar_title ) ) {
 198
 199                         $attribs['title'] = Title::makeTitle( $row->ar_namespace, $row->ar_title );
 200                 }
 201
 202                 if ( isset( $row->ar_text ) && !$row->ar_text_id ) {
 203                         // Pre-1.5 ar_text row
 204                         $attribs['text'] = self::getRevisionText( $row, 'ar_' );
 205                         if ( $attribs['text'] === false ) {
 206                                 throw new MWException( 'Unable to load text from archive row (possibly bug 22624)' );
 207                         }
 208                 }
 209                 return new self( $attribs );
 210         }
 211
 212         /**
 213          * @since 1.19
 214          *
 215          * @param object $row
 216          * @return Revision
 217          */
 218         public static function newFromRow( $row ) {
 219                 return new self( $row );
 220         }
 221
 222         /**
 223          * Load a page revision from a given revision ID number.
 224          * Returns null if no such revision can be found.
 225          *
 226          * @param DatabaseBase $db
 227          * @param int $id
 228          * @return Revision|null
 229          */
 230         public static function loadFromId( $db, $id ) {
 231                 return self::loadFromConds( $db, array( 'rev_id' => intval( $id ) ) );
 232         }
 233
 234         /**
 235          * Load either the current, or a specified, revision
 236          * that's attached to a given page. If not attached
 237          * to that page, will return null.
 238          *
 239          * @param DatabaseBase $db
 240          * @param int $pageid
 241          * @param int $id
 242          * @return Revision|null
 243          */
 244         public static function loadFromPageId( $db, $pageid, $id = 0 ) {
 245                 $conds = array( 'rev_page' => intval( $pageid ), 'page_id' => intval( $pageid ) );
 246                 if ( $id ) {
 247                         $conds['rev_id'] = intval( $id );
 248                 } else {
 249                         $conds[] = 'rev_id=page_latest';
 250                 }
 251                 return self::loadFromConds( $db, $conds );
 252         }
 253
 254         /**
 255          * Load either the current, or a specified, revision
 256          * that's attached to a given page. If not attached
 257          * to that page, will return null.
 258          *
 259          * @param DatabaseBase $db
 260          * @param Title $title
 261          * @param int $id
 262          * @return Revision|null
 263          */
 264         public static function loadFromTitle( $db, $title, $id = 0 ) {
 265                 if ( $id ) {
 266                         $matchId = intval( $id );
 267                 } else {
 268                         $matchId = 'page_latest';
 269                 }
 270                 return self::loadFromConds( $db,
 271                         array(
 272                                 "rev_id=$matchId",
 273                                 'page_namespace' => $title->getNamespace(),
 274                                 'page_title' => $title->getDBkey()
 275                         )
 276                 );
 277         }
 278
 279         /**
 280          * Load the revision for the given title with the given timestamp.
 281          * WARNING: Timestamps may in some circumstances not be unique,
 282          * so this isn't the best key to use.
 283          *
 284          * @param DatabaseBase $db
 285          * @param Title $title
 286          * @param string $timestamp
 287          * @return Revision|null
 288          */
 289         public static function loadFromTimestamp( $db, $title, $timestamp ) {
 290                 return self::loadFromConds( $db,
 291                         array(
 292                                 'rev_timestamp' => $db->timestamp( $timestamp ),
 293                                 'page_namespace' => $title->getNamespace(),
 294                                 'page_title' => $title->getDBkey()
 295                         )
 296                 );
 297         }
 298
 299         /**
 300          * Given a set of conditions, fetch a revision.
 301          *
 302          * @param array $conditions
 303          * @param int $flags (optional)
 304          * @return Revision|null
 305          */
 306         private static function newFromConds( $conditions, $flags = 0 ) {
 307                 $db = wfGetDB( ( $flags & self::READ_LATEST ) ? DB_MASTER : DB_SLAVE );
 308                 $rev = self::loadFromConds( $db, $conditions, $flags );
 309                 if ( $rev ) {
 310                         $rev->mQueryFlags = $flags;
 311                 }
 312                 return $rev;
 313         }
 314
 315         /**
 316          * Given a set of conditions, fetch a revision from
 317          * the given database connection.
 318          *
 319          * @param DatabaseBase $db
 320          * @param array $conditions
 321          * @param int $flags (optional)
 322          * @return Revision|null
 323          */
 324         private static function loadFromConds( $db, $conditions, $flags = 0 ) {
 325                 $res = self::fetchFromConds( $db, $conditions, $flags );
 326                 if ( $res ) {
 327                         $row = $res->fetchObject();
 328                         if ( $row ) {
 329                                 $ret = new Revision( $row );
 330                                 return $ret;
 331                         }
 332                 }
 333                 $ret = null;
 334                 return $ret;
 335         }
 336
 337         /**
 338          * Return a wrapper for a series of database rows to
 339          * fetch all of a given page's revisions in turn.
 340          * Each row can be fed to the constructor to get objects.
 341          *
 342          * @param Title $title
 343          * @return ResultWrapper
 344          */
 345         public static function fetchRevision( $title ) {
 346                 return self::fetchFromConds(
 347                         wfGetDB( DB_SLAVE ),
 348                         array(
 349                                 'rev_id=page_latest',
 350                                 'page_namespace' => $title->getNamespace(),
 351                                 'page_title' => $title->getDBkey()
 352                         )
 353                 );
 354         }
 355
 356         /**
 357          * Given a set of conditions, return a ResultWrapper
 358          * which will return matching database rows with the
 359          * fields necessary to build Revision objects.
 360          *
 361          * @param DatabaseBase $db
 362          * @param array $conditions
 363          * @param int $flags (optional)
 364          * @return ResultWrapper
 365          */
 366         private static function fetchFromConds( $db, $conditions, $flags = 0 ) {
 367                 $fields = array_merge(
 368                         self::selectFields(),
 369                         self::selectPageFields(),
 370                         self::selectUserFields()
 371                 );
 372                 $options = array( 'LIMIT' => 1 );
 373                 if ( ( $flags & self::READ_LOCKING ) == self::READ_LOCKING ) {
 374                         $options[] = 'FOR UPDATE';
 375                 }
 376                 return $db->select(
 377                         array( 'revision', 'page', 'user' ),
 378                         $fields,
 379                         $conditions,
 380                         __METHOD__,
 381                         $options,
 382                         array( 'page' => self::pageJoinCond(), 'user' => self::userJoinCond() )
 383                 );
 384         }
 385
 386         /**
 387          * Return the value of a select() JOIN conds array for the user table.
 388          * This will get user table rows for logged-in users.
 389          * @since 1.19
 390          * @return array
 391          */
 392         public static function userJoinCond() {
 393                 return array( 'LEFT JOIN', array( 'rev_user != 0', 'user_id = rev_user' ) );
 394         }
 395
 396         /**
 397          * Return the value of a select() page conds array for the page table.
 398          * This will assure that the revision(s) are not orphaned from live pages.
 399          * @since 1.19
 400          * @return array
 401          */
 402         public static function pageJoinCond() {
 403                 return array( 'INNER JOIN', array( 'page_id = rev_page' ) );
 404         }
 405
 406         /**
 407          * Return the list of revision fields that should be selected to create
 408          * a new revision.
 409          * @return array
 410          */
 411         public static function selectFields() {
 412                 global $wgContentHandlerUseDB;
 413
 414                 $fields = array(
 415                         'rev_id',
 416                         'rev_page',
 417                         'rev_text_id',
 418                         'rev_timestamp',
 419                         'rev_comment',
 420                         'rev_user_text',
 421                         'rev_user',
 422                         'rev_minor_edit',
 423                         'rev_deleted',
 424                         'rev_len',
 425                         'rev_parent_id',
 426                         'rev_sha1',
 427                 );
 428
 429                 if ( $wgContentHandlerUseDB ) {
 430                         $fields[] = 'rev_content_format';
 431                         $fields[] = 'rev_content_model';
 432                 }
 433
 434                 return $fields;
 435         }
 436
 437         /**
 438          * Return the list of revision fields that should be selected to create
 439          * a new revision from an archive row.
 440          * @return array
 441          */
 442         public static function selectArchiveFields() {
 443                 global $wgContentHandlerUseDB;
 444                 $fields = array(
 445                         'ar_id',
 446                         'ar_page_id',
 447                         'ar_rev_id',
 448                         'ar_text',
 449                         'ar_text_id',
 450                         'ar_timestamp',
 451                         'ar_comment',
 452                         'ar_user_text',
 453                         'ar_user',
 454                         'ar_minor_edit',
 455                         'ar_deleted',
 456                         'ar_len',
 457                         'ar_parent_id',
 458                         'ar_sha1',
 459                 );
 460
 461                 if ( $wgContentHandlerUseDB ) {
 462                         $fields[] = 'ar_content_format';
 463                         $fields[] = 'ar_content_model';
 464                 }
 465                 return $fields;
 466         }
 467
 468         /**
 469          * Return the list of text fields that should be selected to read the
 470          * revision text
 471          * @return array
 472          */
 473         public static function selectTextFields() {
 474                 return array(
 475                         'old_text',
 476                         'old_flags'
 477                 );
 478         }
 479
 480         /**
 481          * Return the list of page fields that should be selected from page table
 482          * @return array
 483          */
 484         public static function selectPageFields() {
 485                 return array(
 486                         'page_namespace',
 487                         'page_title',
 488                         'page_id',
 489                         'page_latest',
 490                         'page_is_redirect',
 491                         'page_len',
 492                 );
 493         }
 494
 495         /**
 496          * Return the list of user fields that should be selected from user table
 497          * @return array
 498          */
 499         public static function selectUserFields() {
 500                 return array( 'user_name' );
 501         }
 502
 503         /**
 504          * Do a batched query to get the parent revision lengths
 505          * @param DatabaseBase $db
 506          * @param array $revIds
 507          * @return array
 508          */
 509         public static function getParentLengths( $db, array $revIds ) {
 510                 $revLens = array();
 511                 if ( !$revIds ) {
 512                         return $revLens; // empty
 513                 }
 514                 $res = $db->select( 'revision',
 515                         array( 'rev_id', 'rev_len' ),
 516                         array( 'rev_id' => $revIds ),
 517                         __METHOD__ );
 518                 foreach ( $res as $row ) {
 519                         $revLens[$row->rev_id] = $row->rev_len;
 520                 }
 521                 return $revLens;
 522         }
 523
 524         /**
 525          * Constructor
 526          *
 527          * @param object|array $row Either a database row or an array
 528          * @throws MWException
 529          * @access private
 530          */
 531         function __construct( $row ) {
 532                 if ( is_object( $row ) ) {
 533                         $this->mId = intval( $row->rev_id );
 534                         $this->mPage = intval( $row->rev_page );
 535                         $this->mTextId = intval( $row->rev_text_id );
 536                         $this->mComment = $row->rev_comment;
 537                         $this->mUser = intval( $row->rev_user );
 538                         $this->mMinorEdit = intval( $row->rev_minor_edit );
 539                         $this->mTimestamp = $row->rev_timestamp;
 540                         $this->mDeleted = intval( $row->rev_deleted );
 541
 542                         if ( !isset( $row->rev_parent_id ) ) {
 543                                 $this->mParentId = null;
 544                         } else {
 545                                 $this->mParentId = intval( $row->rev_parent_id );
 546                         }
 547
 548                         if ( !isset( $row->rev_len ) ) {
 549                                 $this->mSize = null;
 550                         } else {
 551                                 $this->mSize = intval( $row->rev_len );
 552                         }
 553
 554                         if ( !isset( $row->rev_sha1 ) ) {
 555                                 $this->mSha1 = null;
 556                         } else {
 557                                 $this->mSha1 = $row->rev_sha1;
 558                         }
 559
 560                         if ( isset( $row->page_latest ) ) {
 561                                 $this->mCurrent = ( $row->rev_id == $row->page_latest );
 562                                 $this->mTitle = Title::newFromRow( $row );
 563                         } else {
 564                                 $this->mCurrent = false;
 565                                 $this->mTitle = null;
 566                         }
 567
 568                         if ( !isset( $row->rev_content_model ) ) {
 569                                 $this->mContentModel = null; # determine on demand if needed
 570                         } else {
 571                                 $this->mContentModel = strval( $row->rev_content_model );
 572                         }
 573
 574                         if ( !isset( $row->rev_content_format ) ) {
 575                                 $this->mContentFormat = null; # determine on demand if needed
 576                         } else {
 577                                 $this->mContentFormat = strval( $row->rev_content_format );
 578                         }
 579
 580                         // Lazy extraction...
 581                         $this->mText = null;
 582                         if ( isset( $row->old_text ) ) {
 583                                 $this->mTextRow = $row;
 584                         } else {
 585                                 // 'text' table row entry will be lazy-loaded
 586                                 $this->mTextRow = null;
 587                         }
 588
 589                         // Use user_name for users and rev_user_text for IPs...
 590                         $this->mUserText = null; // lazy load if left null
 591                         if ( $this->mUser == 0 ) {
 592                                 $this->mUserText = $row->rev_user_text; // IP user
 593                         } elseif ( isset( $row->user_name ) ) {
 594                                 $this->mUserText = $row->user_name; // logged-in user
 595                         }
 596                         $this->mOrigUserText = $row->rev_user_text;
 597                 } elseif ( is_array( $row ) ) {
 598                         // Build a new revision to be saved...
 599                         global $wgUser; // ugh
 600
 601                         # if we have a content object, use it to set the model and type
 602                         if ( !empty( $row['content'] ) ) {
 603                                 // @todo when is that set? test with external store setup! check out insertOn() [dk]
 604                                 if ( !empty( $row['text_id'] ) ) {
 605                                         throw new MWException( "Text already stored in external store (id {$row['text_id']}), " .
 606                                                 "can't serialize content object" );
 607                                 }
 608
 609                                 $row['content_model'] = $row['content']->getModel();
 610                                 # note: mContentFormat is initializes later accordingly
 611                                 # note: content is serialized later in this method!
 612                                 # also set text to null?
 613                         }
 614
 615                         $this->mId = isset( $row['id'] ) ? intval( $row['id'] ) : null;
 616                         $this->mPage = isset( $row['page'] ) ? intval( $row['page'] ) : null;
 617                         $this->mTextId = isset( $row['text_id'] ) ? intval( $row['text_id'] ) : null;
 618                         $this->mUserText = isset( $row['user_text'] )
 619                                 ? strval( $row['user_text'] ) : $wgUser->getName();
 620                         $this->mUser = isset( $row['user'] ) ? intval( $row['user'] ) : $wgUser->getId();
 621                         $this->mMinorEdit = isset( $row['minor_edit'] ) ? intval( $row['minor_edit'] ) : 0;
 622                         $this->mTimestamp = isset( $row['timestamp'] )
 623                                 ? strval( $row['timestamp'] ) : wfTimestampNow();
 624                         $this->mDeleted = isset( $row['deleted'] ) ? intval( $row['deleted'] ) : 0;
 625                         $this->mSize = isset( $row['len'] ) ? intval( $row['len'] ) : null;
 626                         $this->mParentId = isset( $row['parent_id'] ) ? intval( $row['parent_id'] ) : null;
 627                         $this->mSha1 = isset( $row['sha1'] ) ? strval( $row['sha1'] ) : null;
 628
 629                         $this->mContentModel = isset( $row['content_model'] )
 630                                 ? strval( $row['content_model'] ) : null;
 631                         $this->mContentFormat = isset( $row['content_format'] )
 632                                 ? strval( $row['content_format'] ) : null;
 633
 634                         // Enforce spacing trimming on supplied text
 635                         $this->mComment = isset( $row['comment'] ) ? trim( strval( $row['comment'] ) ) : null;
 636                         $this->mText = isset( $row['text'] ) ? rtrim( strval( $row['text'] ) ) : null;
 637                         $this->mTextRow = null;
 638
 639                         $this->mTitle = isset( $row['title'] ) ? $row['title'] : null;
 640
 641                         // if we have a Content object, override mText and mContentModel
 642                         if ( !empty( $row['content'] ) ) {
 643                                 if ( !( $row['content'] instanceof Content ) ) {
 644                                         throw new MWException( '`content` field must contain a Content object.' );
 645                                 }
 646
 647                                 $handler = $this->getContentHandler();
 648                                 $this->mContent = $row['content'];
 649
 650                                 $this->mContentModel = $this->mContent->getModel();
 651                                 $this->mContentHandler = null;
 652
 653                                 $this->mText = $handler->serializeContent( $row['content'], $this->getContentFormat() );
 654                         } elseif ( $this->mText !== null ) {
 655                                 $handler = $this->getContentHandler();
 656                                 $this->mContent = $handler->unserializeContent( $this->mText );
 657                         }
 658
 659                         // If we have a Title object, make sure it is consistent with mPage.
 660                         if ( $this->mTitle && $this->mTitle->exists() ) {
 661                                 if ( $this->mPage === null ) {
 662                                         // if the page ID wasn't known, set it now
 663                                         $this->mPage = $this->mTitle->getArticleID();
 664                                 } elseif ( $this->mTitle->getArticleID() !== $this->mPage ) {
 665                                         // Got different page IDs. This may be legit (e.g. during undeletion),
 666                                         // but it seems worth mentioning it in the log.
 667                                         wfDebug( "Page ID " . $this->mPage . " mismatches the ID " .
 668                                                 $this->mTitle->getArticleID() . " provided by the Title object." );
 669                                 }
 670                         }
 671
 672                         $this->mCurrent = false;
 673
 674                         // If we still have no length, see it we have the text to figure it out
 675                         if ( !$this->mSize && $this->mContent !== null ) {
 676                                 $this->mSize = $this->mContent->getSize();
 677                         }
 678
 679                         // Same for sha1
 680                         if ( $this->mSha1 === null ) {
 681                                 $this->mSha1 = $this->mText === null ? null : self::base36Sha1( $this->mText );
 682                         }
 683
 684                         // force lazy init
 685                         $this->getContentModel();
 686                         $this->getContentFormat();
 687                 } else {
 688                         throw new MWException( 'Revision constructor passed invalid row format.' );
 689                 }
 690                 $this->mUnpatrolled = null;
 691         }
 692
 693         /**
 694          * Get revision ID
 695          *
 696          * @return int|null
 697          */
 698         public function getId() {
 699                 return $this->mId;
 700         }
 701
 702         /**
 703          * Set the revision ID
 704          *
 705          * @since 1.19
 706          * @param int $id
 707          */
 708         public function setId( $id ) {
 709                 $this->mId = $id;
 710         }
 711
 712         /**
 713          * Get text row ID
 714          *
 715          * @return int|null
 716          */
 717         public function getTextId() {
 718                 return $this->mTextId;
 719         }
 720
 721         /**
 722          * Get parent revision ID (the original previous page revision)
 723          *
 724          * @return int|null
 725          */
 726         public function getParentId() {
 727                 return $this->mParentId;
 728         }
 729
 730         /**
 731          * Returns the length of the text in this revision, or null if unknown.
 732          *
 733          * @return int|null
 734          */
 735         public function getSize() {
 736                 return $this->mSize;
 737         }
 738
 739         /**
 740          * Returns the base36 sha1 of the text in this revision, or null if unknown.
 741          *
 742          * @return string|null
 743          */
 744         public function getSha1() {
 745                 return $this->mSha1;
 746         }
 747
 748         /**
 749          * Returns the title of the page associated with this entry or null.
 750          *
 751          * Will do a query, when title is not set and id is given.
 752          *
 753          * @return Title|null
 754          */
 755         public function getTitle() {
 756                 if ( $this->mTitle !== null ) {
 757                         return $this->mTitle;
 758                 }
 759                 //rev_id is defined as NOT NULL, but this revision may not yet have been inserted.
 760                 if ( $this->mId !== null ) {
 761                         $dbr = wfGetDB( DB_SLAVE );
 762                         $row = $dbr->selectRow(
 763                                 array( 'page', 'revision' ),
 764                                 self::selectPageFields(),
 765                                 array( 'page_id=rev_page',
 766                                         'rev_id' => $this->mId ),
 767                                 __METHOD__ );
 768                         if ( $row ) {
 769                                 $this->mTitle = Title::newFromRow( $row );
 770                         }
 771                 }
 772
 773                 if ( !$this->mTitle && $this->mPage !== null && $this->mPage > 0 ) {
 774                         $this->mTitle = Title::newFromID( $this->mPage );
 775                 }
 776
 777                 return $this->mTitle;
 778         }
 779
 780         /**
 781          * Set the title of the revision
 782          *
 783          * @param Title $title
 784          */
 785         public function setTitle( $title ) {
 786                 $this->mTitle = $title;
 787         }
 788
 789         /**
 790          * Get the page ID
 791          *
 792          * @return int|null
 793          */
 794         public function getPage() {
 795                 return $this->mPage;
 796         }
 797
 798         /**
 799          * Fetch revision's user id if it's available to the specified audience.
 800          * If the specified audience does not have access to it, zero will be
 801          * returned.
 802          *
 803          * @param int $audience One of:
 804          *   Revision::FOR_PUBLIC       to be displayed to all users
 805          *   Revision::FOR_THIS_USER    to be displayed to the given user
 806          *   Revision::RAW              get the ID regardless of permissions
 807          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 808          *   to the $audience parameter
 809          * @return int
 810          */
 811         public function getUser( $audience = self::FOR_PUBLIC, User $user = null ) {
 812                 if ( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_USER ) ) {
 813                         return 0;
 814                 } elseif ( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_USER, $user ) ) {
 815                         return 0;
 816                 } else {
 817                         return $this->mUser;
 818                 }
 819         }
 820
 821         /**
 822          * Fetch revision's user id without regard for the current user's permissions
 823          *
 824          * @return string
 825          * @deprecated since 1.25, use getUser( Revision::RAW )
 826          */
 827         public function getRawUser() {
 828                 wfDeprecated( __METHOD__, '1.25' );
 829                 return $this->getUser( self::RAW );
 830         }
 831
 832         /**
 833          * Fetch revision's username if it's available to the specified audience.
 834          * If the specified audience does not have access to the username, an
 835          * empty string will be returned.
 836          *
 837          * @param int $audience One of:
 838          *   Revision::FOR_PUBLIC       to be displayed to all users
 839          *   Revision::FOR_THIS_USER    to be displayed to the given user
 840          *   Revision::RAW              get the text regardless of permissions
 841          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 842          *   to the $audience parameter
 843          * @return string
 844          */
 845         public function getUserText( $audience = self::FOR_PUBLIC, User $user = null ) {
 846                 if ( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_USER ) ) {
 847                         return '';
 848                 } elseif ( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_USER, $user ) ) {
 849                         return '';
 850                 } else {
 851                         if ( $this->mUserText === null ) {
 852                                 $this->mUserText = User::whoIs( $this->mUser ); // load on demand
 853                                 if ( $this->mUserText === false ) {
 854                                         # This shouldn't happen, but it can if the wiki was recovered
 855                                         # via importing revs and there is no user table entry yet.
 856                                         $this->mUserText = $this->mOrigUserText;
 857                                 }
 858                         }
 859                         return $this->mUserText;
 860                 }
 861         }
 862
 863         /**
 864          * Fetch revision's username without regard for view restrictions
 865          *
 866          * @return string
 867          * @deprecated since 1.25, use getUserText( Revision::RAW )
 868          */
 869         public function getRawUserText() {
 870                 wfDeprecated( __METHOD__, '1.25' );
 871                 return $this->getUserText( self::RAW );
 872         }
 873
 874         /**
 875          * Fetch revision comment if it's available to the specified audience.
 876          * If the specified audience does not have access to the comment, an
 877          * empty string will be returned.
 878          *
 879          * @param int $audience One of:
 880          *   Revision::FOR_PUBLIC       to be displayed to all users
 881          *   Revision::FOR_THIS_USER    to be displayed to the given user
 882          *   Revision::RAW              get the text regardless of permissions
 883          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 884          *   to the $audience parameter
 885          * @return string
 886          */
 887         function getComment( $audience = self::FOR_PUBLIC, User $user = null ) {
 888                 if ( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_COMMENT ) ) {
 889                         return '';
 890                 } elseif ( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_COMMENT, $user ) ) {
 891                         return '';
 892                 } else {
 893                         return $this->mComment;
 894                 }
 895         }
 896
 897         /**
 898          * Fetch revision comment without regard for the current user's permissions
 899          *
 900          * @return string
 901          * @deprecated since 1.25, use getComment( Revision::RAW )
 902          */
 903         public function getRawComment() {
 904                 wfDeprecated( __METHOD__, '1.25' );
 905                 return $this->getComment( self::RAW );
 906         }
 907
 908         /**
 909          * @return bool
 910          */
 911         public function isMinor() {
 912                 return (bool)$this->mMinorEdit;
 913         }
 914
 915         /**
 916          * @return int Rcid of the unpatrolled row, zero if there isn't one
 917          */
 918         public function isUnpatrolled() {
 919                 if ( $this->mUnpatrolled !== null ) {
 920                         return $this->mUnpatrolled;
 921                 }
 922                 $rc = $this->getRecentChange();
 923                 if ( $rc && $rc->getAttribute( 'rc_patrolled' ) == 0 ) {
 924                         $this->mUnpatrolled = $rc->getAttribute( 'rc_id' );
 925                 } else {
 926                         $this->mUnpatrolled = 0;
 927                 }
 928                 return $this->mUnpatrolled;
 929         }
 930
 931         /**
 932          * Get the RC object belonging to the current revision, if there's one
 933          *
 934          * @since 1.22
 935          * @return RecentChange|null
 936          */
 937         public function getRecentChange() {
 938                 $dbr = wfGetDB( DB_SLAVE );
 939                 return RecentChange::newFromConds(
 940                         array(
 941                                 'rc_user_text' => $this->getUserText( Revision::RAW ),
 942                                 'rc_timestamp' => $dbr->timestamp( $this->getTimestamp() ),
 943                                 'rc_this_oldid' => $this->getId()
 944                         ),
 945                         __METHOD__
 946                 );
 947         }
 948
 949         /**
 950          * @param int $field One of DELETED_* bitfield constants
 951          *
 952          * @return bool
 953          */
 954         public function isDeleted( $field ) {
 955                 return ( $this->mDeleted & $field ) == $field;
 956         }
 957
 958         /**
 959          * Get the deletion bitfield of the revision
 960          *
 961          * @return int
 962          */
 963         public function getVisibility() {
 964                 return (int)$this->mDeleted;
 965         }
 966
 967         /**
 968          * Fetch revision text if it's available to the specified audience.
 969          * If the specified audience does not have the ability to view this
 970          * revision, an empty string will be returned.
 971          *
 972          * @param int $audience One of:
 973          *   Revision::FOR_PUBLIC       to be displayed to all users
 974          *   Revision::FOR_THIS_USER    to be displayed to the given user
 975          *   Revision::RAW              get the text regardless of permissions
 976          * @param User $user User object to check for, only if FOR_THIS_USER is passed
 977          *   to the $audience parameter
 978          *
 979          * @deprecated since 1.21, use getContent() instead
 980          * @todo Replace usage in core
 981          * @return string
 982          */
 983         public function getText( $audience = self::FOR_PUBLIC, User $user = null ) {
 984                 ContentHandler::deprecated( __METHOD__, '1.21' );
 985
 986                 $content = $this->getContent( $audience, $user );
 987                 return ContentHandler::getContentText( $content ); # returns the raw content text, if applicable
 988         }
 989
 990         /**
 991          * Fetch revision content if it's available to the specified audience.
 992          * If the specified audience does not have the ability to view this
 993          * revision, null will be returned.
 994          *
 995          * @param int $audience One of:
 996          *   Revision::FOR_PUBLIC       to be displayed to all users
 997          *   Revision::FOR_THIS_USER    to be displayed to $wgUser
 998          *   Revision::RAW              get the text regardless of permissions
 999          * @param User $user User object to check for, only if FOR_THIS_USER is passed
1000          *   to the $audience parameter
1001          * @since 1.21
1002          * @return Content|null
1003          */
1004         public function getContent( $audience = self::FOR_PUBLIC, User $user = null ) {
1005                 if ( $audience == self::FOR_PUBLIC && $this->isDeleted( self::DELETED_TEXT ) ) {
1006                         return null;
1007                 } elseif ( $audience == self::FOR_THIS_USER && !$this->userCan( self::DELETED_TEXT, $user ) ) {
1008                         return null;
1009                 } else {
1010                         return $this->getContentInternal();
1011                 }
1012         }
1013
1014         /**
1015          * Fetch revision text without regard for view restrictions
1016          *
1017          * @return string
1018          *
1019          * @deprecated since 1.21. Instead, use Revision::getContent( Revision::RAW )
1020          *                         or Revision::getSerializedData() as appropriate.
1021          */
1022         public function getRawText() {
1023                 ContentHandler::deprecated( __METHOD__, "1.21" );
1024                 return $this->getText( self::RAW );
1025         }
1026
1027         /**
1028          * Fetch original serialized data without regard for view restrictions
1029          *
1030          * @since 1.21
1031          * @return string
1032          */
1033         public function getSerializedData() {
1034                 if ( $this->mText === null ) {
1035                         $this->mText = $this->loadText();
1036                 }
1037
1038                 return $this->mText;
1039         }
1040
1041         /**
1042          * Gets the content object for the revision (or null on failure).
1043          *
1044          * Note that for mutable Content objects, each call to this method will return a
1045          * fresh clone.
1046          *
1047          * @since 1.21
1048          * @return Content|null The Revision's content, or null on failure.
1049          */
1050         protected function getContentInternal() {
1051                 if ( $this->mContent === null ) {
1052                         // Revision is immutable. Load on demand:
1053                         if ( $this->mText === null ) {
1054                                 $this->mText = $this->loadText();
1055                         }
1056
1057                         if ( $this->mText !== null && $this->mText !== false ) {
1058                                 // Unserialize content
1059                                 $handler = $this->getContentHandler();
1060                                 $format = $this->getContentFormat();
1061
1062                                 $this->mContent = $handler->unserializeContent( $this->mText, $format );
1063                         }
1064                 }
1065
1066                 // NOTE: copy() will return $this for immutable content objects
1067                 return $this->mContent ? $this->mContent->copy() : null;
1068         }
1069
1070         /**
1071          * Returns the content model for this revision.
1072          *
1073          * If no content model was stored in the database, $this->getTitle()->getContentModel() is
1074          * used to determine the content model to use. If no title is know, CONTENT_MODEL_WIKITEXT
1075          * is used as a last resort.
1076          *
1077          * @return string The content model id associated with this revision,
1078          *     see the CONTENT_MODEL_XXX constants.
1079          **/
1080         public function getContentModel() {
1081                 if ( !$this->mContentModel ) {
1082                         $title = $this->getTitle();
1083                         $this->mContentModel = ( $title ? $title->getContentModel() : CONTENT_MODEL_WIKITEXT );
1084
1085                         assert( !empty( $this->mContentModel ) );
1086                 }
1087
1088                 return $this->mContentModel;
1089         }
1090
1091         /**
1092          * Returns the content format for this revision.
1093          *
1094          * If no content format was stored in the database, the default format for this
1095          * revision's content model is returned.
1096          *
1097          * @return string The content format id associated with this revision,
1098          *     see the CONTENT_FORMAT_XXX constants.
1099          **/
1100         public function getContentFormat() {
1101                 if ( !$this->mContentFormat ) {
1102                         $handler = $this->getContentHandler();
1103                         $this->mContentFormat = $handler->getDefaultFormat();
1104
1105                         assert( !empty( $this->mContentFormat ) );
1106                 }
1107
1108                 return $this->mContentFormat;
1109         }
1110
1111         /**
1112          * Returns the content handler appropriate for this revision's content model.
1113          *
1114          * @throws MWException
1115          * @return ContentHandler
1116          */
1117         public function getContentHandler() {
1118                 if ( !$this->mContentHandler ) {
1119                         $model = $this->getContentModel();
1120                         $this->mContentHandler = ContentHandler::getForModelID( $model );
1121
1122                         $format = $this->getContentFormat();
1123
1124                         if ( !$this->mContentHandler->isSupportedFormat( $format ) ) {
1125                                 throw new MWException( "Oops, the content format $format is not supported for "
1126                                         . "this content model, $model" );
1127                         }
1128                 }
1129
1130                 return $this->mContentHandler;
1131         }
1132
1133         /**
1134          * @return string
1135          */
1136         public function getTimestamp() {
1137                 return wfTimestamp( TS_MW, $this->mTimestamp );
1138         }
1139
1140         /**
1141          * @return bool
1142          */
1143         public function isCurrent() {
1144                 return $this->mCurrent;
1145         }
1146
1147         /**
1148          * Get previous revision for this title
1149          *
1150          * @return Revision|null
1151          */
1152         public function getPrevious() {
1153                 if ( $this->getTitle() ) {
1154                         $prev = $this->getTitle()->getPreviousRevisionID( $this->getId() );
1155                         if ( $prev ) {
1156                                 return self::newFromTitle( $this->getTitle(), $prev );
1157                         }
1158                 }
1159                 return null;
1160         }
1161
1162         /**
1163          * Get next revision for this title
1164          *
1165          * @return Revision|null
1166          */
1167         public function getNext() {
1168                 if ( $this->getTitle() ) {
1169                         $next = $this->getTitle()->getNextRevisionID( $this->getId() );
1170                         if ( $next ) {
1171                                 return self::newFromTitle( $this->getTitle(), $next );
1172                         }
1173                 }
1174                 return null;
1175         }
1176
1177         /**
1178          * Get previous revision Id for this page_id
1179          * This is used to populate rev_parent_id on save
1180          *
1181          * @param DatabaseBase $db
1182          * @return int
1183          */
1184         private function getPreviousRevisionId( $db ) {
1185                 if ( $this->mPage === null ) {
1186                         return 0;
1187                 }
1188                 # Use page_latest if ID is not given
1189                 if ( !$this->mId ) {
1190                         $prevId = $db->selectField( 'page', 'page_latest',
1191                                 array( 'page_id' => $this->mPage ),
1192                                 __METHOD__ );
1193                 } else {
1194                         $prevId = $db->selectField( 'revision', 'rev_id',
1195                                 array( 'rev_page' => $this->mPage, 'rev_id < ' . $this->mId ),
1196                                 __METHOD__,
1197                                 array( 'ORDER BY' => 'rev_id DESC' ) );
1198                 }
1199                 return intval( $prevId );
1200         }
1201
1202         /**
1203          * Get revision text associated with an old or archive row
1204          * $row is usually an object from wfFetchRow(), both the flags and the text
1205          * field must be included.
1206          *
1207          * @param stdClass $row The text data
1208          * @param string $prefix Table prefix (default 'old_')
1209          * @param string|bool $wiki The name of the wiki to load the revision text from
1210          *   (same as the the wiki $row was loaded from) or false to indicate the local
1211          *   wiki (this is the default). Otherwise, it must be a symbolic wiki database
1212          *   identifier as understood by the LoadBalancer class.
1213          * @return string Text the text requested or false on failure
1214          */
1215         public static function getRevisionText( $row, $prefix = 'old_', $wiki = false ) {
1216
1217                 # Get data
1218                 $textField = $prefix . 'text';
1219                 $flagsField = $prefix . 'flags';
1220
1221                 if ( isset( $row->$flagsField ) ) {
1222                         $flags = explode( ',', $row->$flagsField );
1223                 } else {
1224                         $flags = array();
1225                 }
1226
1227                 if ( isset( $row->$textField ) ) {
1228                         $text = $row->$textField;
1229                 } else {
1230                         return false;
1231                 }
1232
1233                 # Use external methods for external objects, text in table is URL-only then
1234                 if ( in_array( 'external', $flags ) ) {
1235                         $url = $text;
1236                         $parts = explode( '://', $url, 2 );
1237                         if ( count( $parts ) == 1 || $parts[1] == '' ) {
1238                                 return false;
1239                         }
1240                         $text = ExternalStore::fetchFromURL( $url, array( 'wiki' => $wiki ) );
1241                 }
1242
1243                 // If the text was fetched without an error, convert it
1244                 if ( $text !== false ) {
1245                         $text = self::decompressRevisionText( $text, $flags );
1246                 }
1247                 return $text;
1248         }
1249
1250         /**
1251          * If $wgCompressRevisions is enabled, we will compress data.
1252          * The input string is modified in place.
1253          * Return value is the flags field: contains 'gzip' if the
1254          * data is compressed, and 'utf-8' if we're saving in UTF-8
1255          * mode.
1256          *
1257          * @param mixed $text Reference to a text
1258          * @return string
1259          */
1260         public static function compressRevisionText( &$text ) {
1261                 global $wgCompressRevisions;
1262                 $flags = array();
1263
1264                 # Revisions not marked this way will be converted
1265                 # on load if $wgLegacyCharset is set in the future.
1266                 $flags[] = 'utf-8';
1267
1268                 if ( $wgCompressRevisions ) {
1269                         if ( function_exists( 'gzdeflate' ) ) {
1270                                 $text = gzdeflate( $text );
1271                                 $flags[] = 'gzip';
1272                         } else {
1273                                 wfDebug( __METHOD__ . " -- no zlib support, not compressing\n" );
1274                         }
1275                 }
1276                 return implode( ',', $flags );
1277         }
1278
1279         /**
1280          * Re-converts revision text according to it's flags.
1281          *
1282          * @param mixed $text Reference to a text
1283          * @param array $flags Compression flags
1284          * @return string|bool Decompressed text, or false on failure
1285          */
1286         public static function decompressRevisionText( $text, $flags ) {
1287                 if ( in_array( 'gzip', $flags ) ) {
1288                         # Deal with optional compression of archived pages.
1289                         # This can be done periodically via maintenance/compressOld.php, and
1290                         # as pages are saved if $wgCompressRevisions is set.
1291                         $text = gzinflate( $text );
1292                 }
1293
1294                 if ( in_array( 'object', $flags ) ) {
1295                         # Generic compressed storage
1296                         $obj = unserialize( $text );
1297                         if ( !is_object( $obj ) ) {
1298                                 // Invalid object
1299                                 return false;
1300                         }
1301                         $text = $obj->getText();
1302                 }
1303
1304                 global $wgLegacyEncoding;
1305                 if ( $text !== false && $wgLegacyEncoding
1306                         && !in_array( 'utf-8', $flags ) && !in_array( 'utf8', $flags )
1307                 ) {
1308                         # Old revisions kept around in a legacy encoding?
1309                         # Upconvert on demand.
1310                         # ("utf8" checked for compatibility with some broken
1311                         #  conversion scripts 2008-12-30)
1312                         global $wgContLang;
1313                         $text = $wgContLang->iconv( $wgLegacyEncoding, 'UTF-8', $text );
1314                 }
1315
1316                 return $text;
1317         }
1318
1319         /**
1320          * Insert a new revision into the database, returning the new revision ID
1321          * number on success and dies horribly on failure.
1322          *
1323          * @param DatabaseBase $dbw (master connection)
1324          * @throws MWException
1325          * @return int
1326          */
1327         public function insertOn( $dbw ) {
1328                 global $wgDefaultExternalStore, $wgContentHandlerUseDB;
1329
1330                 $this->checkContentModel();
1331
1332                 $data = $this->mText;
1333                 $flags = self::compressRevisionText( $data );
1334
1335                 # Write to external storage if required
1336                 if ( $wgDefaultExternalStore ) {
1337                         // Store and get the URL
1338                         $data = ExternalStore::insertToDefault( $data );
1339                         if ( !$data ) {
1340                                 throw new MWException( "Unable to store text to external storage" );
1341                         }
1342                         if ( $flags ) {
1343                                 $flags .= ',';
1344                         }
1345                         $flags .= 'external';
1346                 }
1347
1348                 # Record the text (or external storage URL) to the text table
1349                 if ( $this->mTextId === null ) {
1350                         $old_id = $dbw->nextSequenceValue( 'text_old_id_seq' );
1351                         $dbw->insert( 'text',
1352                                 array(
1353                                         'old_id' => $old_id,
1354                                         'old_text' => $data,
1355                                         'old_flags' => $flags,
1356                                 ), __METHOD__
1357                         );
1358                         $this->mTextId = $dbw->insertId();
1359                 }
1360
1361                 if ( $this->mComment === null ) {
1362                         $this->mComment = "";
1363                 }
1364
1365                 # Record the edit in revisions
1366                 $rev_id = $this->mId !== null
1367                         ? $this->mId
1368                         : $dbw->nextSequenceValue( 'revision_rev_id_seq' );
1369                 $row = array(
1370                         'rev_id'         => $rev_id,
1371                         'rev_page'       => $this->mPage,
1372                         'rev_text_id'    => $this->mTextId,
1373                         'rev_comment'    => $this->mComment,
1374                         'rev_minor_edit' => $this->mMinorEdit ? 1 : 0,
1375                         'rev_user'       => $this->mUser,
1376                         'rev_user_text'  => $this->mUserText,
1377                         'rev_timestamp'  => $dbw->timestamp( $this->mTimestamp ),
1378                         'rev_deleted'    => $this->mDeleted,
1379                         'rev_len'        => $this->mSize,
1380                         'rev_parent_id'  => $this->mParentId === null
1381                                 ? $this->getPreviousRevisionId( $dbw )
1382                                 : $this->mParentId,
1383                         'rev_sha1'       => $this->mSha1 === null
1384                                 ? Revision::base36Sha1( $this->mText )
1385                                 : $this->mSha1,
1386                 );
1387
1388                 if ( $wgContentHandlerUseDB ) {
1389                         //NOTE: Store null for the default model and format, to save space.
1390                         //XXX: Makes the DB sensitive to changed defaults.
1391                         // Make this behavior optional? Only in miser mode?
1392
1393                         $model = $this->getContentModel();
1394                         $format = $this->getContentFormat();
1395
1396                         $title = $this->getTitle();
1397
1398                         if ( $title === null ) {
1399                                 throw new MWException( "Insufficient information to determine the title of the "
1400                                         . "revision's page!" );
1401                         }
1402
1403                         $defaultModel = ContentHandler::getDefaultModelFor( $title );
1404                         $defaultFormat = ContentHandler::getForModelID( $defaultModel )->getDefaultFormat();
1405
1406                         $row['rev_content_model'] = ( $model === $defaultModel ) ? null : $model;
1407                         $row['rev_content_format'] = ( $format === $defaultFormat ) ? null : $format;
1408                 }
1409
1410                 $dbw->insert( 'revision', $row, __METHOD__ );
1411
1412                 $this->mId = $rev_id !== null ? $rev_id : $dbw->insertId();
1413
1414                 Hooks::run( 'RevisionInsertComplete', array( &$this, $data, $flags ) );
1415
1416                 return $this->mId;
1417         }
1418
1419         protected function checkContentModel() {
1420                 global $wgContentHandlerUseDB;
1421
1422                 $title = $this->getTitle(); //note: may return null for revisions that have not yet been inserted.
1423
1424                 $model = $this->getContentModel();
1425                 $format = $this->getContentFormat();
1426                 $handler = $this->getContentHandler();
1427
1428                 if ( !$handler->isSupportedFormat( $format ) ) {
1429                         $t = $title->getPrefixedDBkey();
1430
1431                         throw new MWException( "Can't use format $format with content model $model on $t" );
1432                 }
1433
1434                 if ( !$wgContentHandlerUseDB && $title ) {
1435                         // if $wgContentHandlerUseDB is not set,
1436                         // all revisions must use the default content model and format.
1437
1438                         $defaultModel = ContentHandler::getDefaultModelFor( $title );
1439                         $defaultHandler = ContentHandler::getForModelID( $defaultModel );
1440                         $defaultFormat = $defaultHandler->getDefaultFormat();
1441
1442                         if ( $this->getContentModel() != $defaultModel ) {
1443                                 $t = $title->getPrefixedDBkey();
1444
1445                                 throw new MWException( "Can't save non-default content model with "
1446                                         . "\$wgContentHandlerUseDB disabled: model is $model, "
1447                                         . "default for $t is $defaultModel" );
1448                         }
1449
1450                         if ( $this->getContentFormat() != $defaultFormat ) {
1451                                 $t = $title->getPrefixedDBkey();
1452
1453                                 throw new MWException( "Can't use non-default content format with "
1454                                         . "\$wgContentHandlerUseDB disabled: format is $format, "
1455                                         . "default for $t is $defaultFormat" );
1456                         }
1457                 }
1458
1459                 $content = $this->getContent( Revision::RAW );
1460
1461                 if ( !$content || !$content->isValid() ) {
1462                         $t = $title->getPrefixedDBkey();
1463
1464                         throw new MWException( "Content of $t is not valid! Content model is $model" );
1465                 }
1466         }
1467
1468         /**
1469          * Get the base 36 SHA-1 value for a string of text
1470          * @param string $text
1471          * @return string
1472          */
1473         public static function base36Sha1( $text ) {
1474                 return wfBaseConvert( sha1( $text ), 16, 36, 31 );
1475         }
1476
1477         /**
1478          * Lazy-load the revision's text.
1479          * Currently hardcoded to the 'text' table storage engine.
1480          *
1481          * @return string|bool The revision's text, or false on failure
1482          */
1483         protected function loadText() {
1484
1485                 // Caching may be beneficial for massive use of external storage
1486                 global $wgRevisionCacheExpiry, $wgMemc;
1487                 $textId = $this->getTextId();
1488                 $key = wfMemcKey( 'revisiontext', 'textid', $textId );
1489                 if ( $wgRevisionCacheExpiry ) {
1490                         $text = $wgMemc->get( $key );
1491                         if ( is_string( $text ) ) {
1492                                 wfDebug( __METHOD__ . ": got id $textId from cache\n" );
1493                                 return $text;
1494                         }
1495                 }
1496
1497                 // If we kept data for lazy extraction, use it now...
1498                 if ( $this->mTextRow !== null ) {
1499                         $row = $this->mTextRow;
1500                         $this->mTextRow = null;
1501                 } else {
1502                         $row = null;
1503                 }
1504
1505                 if ( !$row ) {
1506                         // Text data is immutable; check slaves first.
1507                         $dbr = wfGetDB( DB_SLAVE );
1508                         $row = $dbr->selectRow( 'text',
1509                                 array( 'old_text', 'old_flags' ),
1510                                 array( 'old_id' => $textId ),
1511                                 __METHOD__ );
1512                 }
1513
1514                 // Fallback to the master in case of slave lag. Also use FOR UPDATE if it was
1515                 // used to fetch this revision to avoid missing the row due to REPEATABLE-READ.
1516                 $forUpdate = ( $this->mQueryFlags & self::READ_LOCKING == self::READ_LOCKING );
1517                 if ( !$row && ( $forUpdate || wfGetLB()->getServerCount() > 1 ) ) {
1518                         $dbw = wfGetDB( DB_MASTER );
1519                         $row = $dbw->selectRow( 'text',
1520                                 array( 'old_text', 'old_flags' ),
1521                                 array( 'old_id' => $textId ),
1522                                 __METHOD__,
1523                                 $forUpdate ? array( 'FOR UPDATE' ) : array() );
1524                 }
1525
1526                 if ( !$row ) {
1527                         wfDebugLog( 'Revision', "No text row with ID '$textId' (revision {$this->getId()})." );
1528                 }
1529
1530                 $text = self::getRevisionText( $row );
1531                 if ( $row && $text === false ) {
1532                         wfDebugLog( 'Revision', "No blob for text row '$textId' (revision {$this->getId()})." );
1533                 }
1534
1535                 # No negative caching -- negative hits on text rows may be due to corrupted slave servers
1536                 if ( $wgRevisionCacheExpiry && $text !== false ) {
1537                         $wgMemc->set( $key, $text, $wgRevisionCacheExpiry );
1538                 }
1539
1540                 return $text;
1541         }
1542
1543         /**
1544          * Create a new null-revision for insertion into a page's
1545          * history. This will not re-save the text, but simply refer
1546          * to the text from the previous version.
1547          *
1548          * Such revisions can for instance identify page rename
1549          * operations and other such meta-modifications.
1550          *
1551          * @param DatabaseBase $dbw
1552          * @param int $pageId ID number of the page to read from
1553          * @param string $summary Revision's summary
1554          * @param bool $minor Whether the revision should be considered as minor
1555          * @param User|null $user User object to use or null for $wgUser
1556          * @return Revision|null Revision or null on error
1557          */
1558         public static function newNullRevision( $dbw, $pageId, $summary, $minor, $user = null ) {
1559                 global $wgContentHandlerUseDB, $wgContLang;
1560
1561                 $fields = array( 'page_latest', 'page_namespace', 'page_title',
1562                                                 'rev_text_id', 'rev_len', 'rev_sha1' );
1563
1564                 if ( $wgContentHandlerUseDB ) {
1565                         $fields[] = 'rev_content_model';
1566                         $fields[] = 'rev_content_format';
1567                 }
1568
1569                 $current = $dbw->selectRow(
1570                         array( 'page', 'revision' ),
1571                         $fields,
1572                         array(
1573                                 'page_id' => $pageId,
1574                                 'page_latest=rev_id',
1575                                 ),
1576                         __METHOD__ );
1577
1578                 if ( $current ) {
1579                         if ( !$user ) {
1580                                 global $wgUser;
1581                                 $user = $wgUser;
1582                         }
1583
1584                         // Truncate for whole multibyte characters
1585                         $summary = $wgContLang->truncate( $summary, 255 );
1586
1587                         $row = array(
1588                                 'page'       => $pageId,
1589                                 'user_text'  => $user->getName(),
1590                                 'user'       => $user->getId(),
1591                                 'comment'    => $summary,
1592                                 'minor_edit' => $minor,
1593                                 'text_id'    => $current->rev_text_id,
1594                                 'parent_id'  => $current->page_latest,
1595                                 'len'        => $current->rev_len,
1596                                 'sha1'       => $current->rev_sha1
1597                         );
1598
1599                         if ( $wgContentHandlerUseDB ) {
1600                                 $row['content_model'] = $current->rev_content_model;
1601                                 $row['content_format'] = $current->rev_content_format;
1602                         }
1603
1604                         $revision = new Revision( $row );
1605                         $revision->setTitle( Title::makeTitle( $current->page_namespace, $current->page_title ) );
1606                 } else {
1607                         $revision = null;
1608                 }
1609
1610                 return $revision;
1611         }
1612
1613         /**
1614          * Determine if the current user is allowed to view a particular
1615          * field of this revision, if it's marked as deleted.
1616          *
1617          * @param int $field One of self::DELETED_TEXT,
1618          *                              self::DELETED_COMMENT,
1619          *                              self::DELETED_USER
1620          * @param User|null $user User object to check, or null to use $wgUser
1621          * @return bool
1622          */
1623         public function userCan( $field, User $user = null ) {
1624                 return self::userCanBitfield( $this->mDeleted, $field, $user );
1625         }
1626
1627         /**
1628          * Determine if the current user is allowed to view a particular
1629          * field of this revision, if it's marked as deleted. This is used
1630          * by various classes to avoid duplication.
1631          *
1632          * @param int $bitfield Current field
1633          * @param int $field One of self::DELETED_TEXT = File::DELETED_FILE,
1634          *                               self::DELETED_COMMENT = File::DELETED_COMMENT,
1635          *                               self::DELETED_USER = File::DELETED_USER
1636          * @param User|null $user User object to check, or null to use $wgUser
1637          * @param Title|null $title A Title object to check for per-page restrictions on,
1638          *                          instead of just plain userrights
1639          * @return bool
1640          */
1641         public static function userCanBitfield( $bitfield, $field, User $user = null,
1642                 Title $title = null
1643         ) {
1644                 if ( $bitfield & $field ) { // aspect is deleted
1645                         if ( $user === null ) {
1646                                 global $wgUser;
1647                                 $user = $wgUser;
1648                         }
1649                         if ( $bitfield & self::DELETED_RESTRICTED ) {
1650                                 $permissions = array( 'suppressrevision', 'viewsuppressed' );
1651                         } elseif ( $field & self::DELETED_TEXT ) {
1652                                 $permissions = array( 'deletedtext' );
1653                         } else {
1654                                 $permissions = array( 'deletedhistory' );
1655                         }
1656                         $permissionlist = implode( ', ', $permissions );
1657                         if ( $title === null ) {
1658                                 wfDebug( "Checking for $permissionlist due to $field match on $bitfield\n" );
1659                                 return call_user_func_array( array( $user, 'isAllowedAny' ), $permissions );
1660                         } else {
1661                                 $text = $title->getPrefixedText();
1662                                 wfDebug( "Checking for $permissionlist on $text due to $field match on $bitfield\n" );
1663                                 foreach ( $permissions as $perm ) {
1664                                         if ( $title->userCan( $perm, $user ) ) {
1665                                                 return true;
1666                                         }
1667                                 }
1668                                 return false;
1669                         }
1670                 } else {
1671                         return true;
1672                 }
1673         }
1674
1675         /**
1676          * Get rev_timestamp from rev_id, without loading the rest of the row
1677          *
1678          * @param Title $title
1679          * @param int $id
1680          * @return string|bool False if not found
1681          */
1682         static function getTimestampFromId( $title, $id, $flags = 0 ) {
1683                 $db = ( $flags & self::READ_LATEST )
1684                         ? wfGetDB( DB_MASTER )
1685                         : wfGetDB( DB_SLAVE );
1686                 // Casting fix for databases that can't take '' for rev_id
1687                 if ( $id == '' ) {
1688                         $id = 0;
1689                 }
1690                 $conds = array( 'rev_id' => $id );
1691                 $conds['rev_page'] = $title->getArticleID();
1692                 $timestamp = $db->selectField( 'revision', 'rev_timestamp', $conds, __METHOD__ );
1693
1694                 return ( $timestamp !== false ) ? wfTimestamp( TS_MW, $timestamp ) : false;
1695         }
1696
1697         /**
1698          * Get count of revisions per page...not very efficient
1699          *
1700          * @param DatabaseBase $db
1701          * @param int $id Page id
1702          * @return int
1703          */
1704         static function countByPageId( $db, $id ) {
1705                 $row = $db->selectRow( 'revision', array( 'revCount' => 'COUNT(*)' ),
1706                         array( 'rev_page' => $id ), __METHOD__ );
1707                 if ( $row ) {
1708                         return $row->revCount;
1709                 }
1710                 return 0;
1711         }
1712
1713         /**
1714          * Get count of revisions per page...not very efficient
1715          *
1716          * @param DatabaseBase $db
1717          * @param Title $title
1718          * @return int
1719          */
1720         static function countByTitle( $db, $title ) {
1721                 $id = $title->getArticleID();
1722                 if ( $id ) {
1723                         return self::countByPageId( $db, $id );
1724                 }
1725                 return 0;
1726         }
1727
1728         /**
1729          * Check if no edits were made by other users since
1730          * the time a user started editing the page. Limit to
1731          * 50 revisions for the sake of performance.
1732          *
1733          * @since 1.20
1734          * @deprecated since 1.24
1735          *
1736          * @param DatabaseBase|int $db The Database to perform the check on. May be given as a
1737          *        Database object or a database identifier usable with wfGetDB.
1738          * @param int $pageId The ID of the page in question
1739          * @param int $userId The ID of the user in question
1740          * @param string $since Look at edits since this time
1741          *
1742          * @return bool True if the given user was the only one to edit since the given timestamp
1743          */
1744         public static function userWasLastToEdit( $db, $pageId, $userId, $since ) {
1745                 if ( !$userId ) {
1746                         return false;
1747                 }
1748
1749                 if ( is_int( $db ) ) {
1750                         $db = wfGetDB( $db );
1751                 }
1752
1753                 $res = $db->select( 'revision',
1754                         'rev_user',
1755                         array(
1756                                 'rev_page' => $pageId,
1757                                 'rev_timestamp > ' . $db->addQuotes( $db->timestamp( $since ) )
1758                         ),
1759                         __METHOD__,
1760                         array( 'ORDER BY' => 'rev_timestamp ASC', 'LIMIT' => 50 ) );
1761                 foreach ( $res as $row ) {
1762                         if ( $row->rev_user != $userId ) {
1763                                 return false;
1764                         }
1765                 }
1766                 return true;
1767         }
1768 }