includes/Revision.php

   1 <?php
   2 /**
   3  * @package MediaWiki
   4  * @todo document
   5  */
   6
   7 /** */
   8 require_once( 'Database.php' );
   9
  10 /**
  11  * @package MediaWiki
  12  * @todo document
  13  */
  14 class Revision {
  15         const MW_REV_DELETED_TEXT       = 1;
  16         const MW_REV_DELETED_COMMENT    = 2;
  17         const MW_REV_DELETED_USER       = 4;
  18         const MW_REV_DELETED_RESTRICTED = 8;
  19
  20         /**
  21          * Load a page revision from a given revision ID number.
  22          * Returns null if no such revision can be found.
  23          *
  24          * @param int $id
  25          * @static
  26          * @access public
  27          */
  28         function newFromId( $id ) {
  29                 return Revision::newFromConds(
  30                         array( 'page_id=rev_page',
  31                                'rev_id' => intval( $id ) ) );
  32         }
  33
  34         /**
  35          * Load either the current, or a specified, revision
  36          * that's attached to a given title. If not attached
  37          * to that title, will return null.
  38          *
  39          * @param Title $title
  40          * @param int $id
  41          * @return Revision
  42          * @access public
  43          * @static
  44          */
  45         function newFromTitle( &$title, $id = 0 ) {
  46                 if( $id ) {
  47                         $matchId = intval( $id );
  48                 } else {
  49                         $matchId = 'page_latest';
  50                 }
  51                 return Revision::newFromConds(
  52                         array( "rev_id=$matchId",
  53                                'page_id=rev_page',
  54                                'page_namespace' => $title->getNamespace(),
  55                                'page_title'     => $title->getDbkey() ) );
  56         }
  57
  58         /**
  59          * Load either the current, or a specified, revision
  60          * that's attached to a given page. If not attached
  61          * to that page, will return null.
  62          *
  63          * @param Database $db
  64          * @param int $pageid
  65          * @param int $id
  66          * @return Revision
  67          * @access public
  68          */
  69         function loadFromPageId( &$db, $pageid, $id = 0 ) {
  70                 $conds=array('page_id=rev_page','rev_page'=>intval( $pageid ), 'page_id'=>intval( $pageid ));
  71                 if( $id ) {
  72                         $conds['rev_id']=intval($id);
  73                 } else {
  74                         $conds[]='rev_id=page_latest';
  75                 }
  76                 return Revision::loadFromConds( $db, $conds );
  77         }
  78
  79         /**
  80          * Load either the current, or a specified, revision
  81          * that's attached to a given page. If not attached
  82          * to that page, will return null.
  83          *
  84          * @param Database $db
  85          * @param Title $title
  86          * @param int $id
  87          * @return Revision
  88          * @access public
  89          */
  90         function loadFromTitle( &$db, $title, $id = 0 ) {
  91                 if( $id ) {
  92                         $matchId = intval( $id );
  93                 } else {
  94                         $matchId = 'page_latest';
  95                 }
  96                 return Revision::loadFromConds(
  97                         $db,
  98                         array( "rev_id=$matchId",
  99                                'page_id=rev_page',
 100                                'page_namespace' => $title->getNamespace(),
 101                                'page_title'     => $title->getDbkey() ) );
 102         }
 103
 104         /**
 105          * Load the revision for the given title with the given timestamp.
 106          * WARNING: Timestamps may in some circumstances not be unique,
 107          * so this isn't the best key to use.
 108          *
 109          * @param Database $db
 110          * @param Title $title
 111          * @param string $timestamp
 112          * @return Revision
 113          * @access public
 114          * @static
 115          */
 116         function loadFromTimestamp( &$db, &$title, $timestamp ) {
 117                 return Revision::loadFromConds(
 118                         $db,
 119                         array( 'rev_timestamp'  => $db->timestamp( $timestamp ),
 120                                'page_id=rev_page',
 121                                'page_namespace' => $title->getNamespace(),
 122                                'page_title'     => $title->getDbkey() ) );
 123         }
 124
 125         /**
 126          * Given a set of conditions, fetch a revision.
 127          *
 128          * @param array $conditions
 129          * @return Revision
 130          * @static
 131          * @access private
 132          */
 133         function newFromConds( $conditions ) {
 134                 $db =& wfGetDB( DB_SLAVE );
 135                 $row = Revision::loadFromConds( $db, $conditions );
 136                 if( is_null( $row ) ) {
 137                         $dbw =& wfGetDB( DB_MASTER );
 138                         $row = Revision::loadFromConds( $dbw, $conditions );
 139                 }
 140                 return $row;
 141         }
 142
 143         /**
 144          * Given a set of conditions, fetch a revision from
 145          * the given database connection.
 146          *
 147          * @param Database $db
 148          * @param array $conditions
 149          * @return Revision
 150          * @static
 151          * @access private
 152          */
 153         function loadFromConds( &$db, $conditions ) {
 154                 $res = Revision::fetchFromConds( $db, $conditions );
 155                 if( $res ) {
 156                         $row = $res->fetchObject();
 157                         $res->free();
 158                         if( $row ) {
 159                                 $ret = new Revision( $row );
 160                                 return $ret;
 161                         }
 162                 }
 163                 $ret = null;
 164                 return $ret;
 165         }
 166
 167         /**
 168          * Return a wrapper for a series of database rows to
 169          * fetch all of a given page's revisions in turn.
 170          * Each row can be fed to the constructor to get objects.
 171          *
 172          * @param Title $title
 173          * @return ResultWrapper
 174          * @static
 175          * @access public
 176          */
 177         function fetchAllRevisions( &$title ) {
 178                 return Revision::fetchFromConds(
 179                         wfGetDB( DB_SLAVE ),
 180                         array( 'page_namespace' => $title->getNamespace(),
 181                                'page_title'     => $title->getDbkey(),
 182                                'page_id=rev_page' ) );
 183         }
 184
 185         /**
 186          * Return a wrapper for a series of database rows to
 187          * fetch all of a given page's revisions in turn.
 188          * Each row can be fed to the constructor to get objects.
 189          *
 190          * @param Title $title
 191          * @return ResultWrapper
 192          * @static
 193          * @access public
 194          */
 195         function fetchRevision( &$title ) {
 196                 return Revision::fetchFromConds(
 197                         wfGetDB( DB_SLAVE ),
 198                         array( 'rev_id=page_latest',
 199                                'page_namespace' => $title->getNamespace(),
 200                                'page_title'     => $title->getDbkey(),
 201                                'page_id=rev_page' ) );
 202         }
 203
 204         /**
 205          * Given a set of conditions, return a ResultWrapper
 206          * which will return matching database rows with the
 207          * fields necessary to build Revision objects.
 208          *
 209          * @param Database $db
 210          * @param array $conditions
 211          * @return ResultWrapper
 212          * @static
 213          * @access private
 214          */
 215         function fetchFromConds( &$db, $conditions ) {
 216                 $res = $db->select(
 217                         array( 'page', 'revision' ),
 218                         array( 'page_namespace',
 219                                'page_title',
 220                                'page_latest',
 221                                'rev_id',
 222                                'rev_page',
 223                                'rev_text_id',
 224                                'rev_comment',
 225                                'rev_user_text',
 226                                'rev_user',
 227                                'rev_minor_edit',
 228                                'rev_timestamp',
 229                                'rev_deleted' ),
 230                         $conditions,
 231                         'Revision::fetchRow',
 232                         array( 'LIMIT' => 1 ) );
 233                 $ret = $db->resultObject( $res );
 234                 return $ret;
 235         }
 236
 237         /**
 238          * @param object $row
 239          * @access private
 240          */
 241         function Revision( $row ) {
 242                 if( is_object( $row ) ) {
 243                         $this->mId        = intval( $row->rev_id );
 244                         $this->mPage      = intval( $row->rev_page );
 245                         $this->mTextId    = intval( $row->rev_text_id );
 246                         $this->mComment   =         $row->rev_comment;
 247                         $this->mUserText  =         $row->rev_user_text;
 248                         $this->mUser      = intval( $row->rev_user );
 249                         $this->mMinorEdit = intval( $row->rev_minor_edit );
 250                         $this->mTimestamp =         $row->rev_timestamp;
 251                         $this->mDeleted   = intval( $row->rev_deleted );
 252
 253                         if( isset( $row->page_latest ) ) {
 254                                 $this->mCurrent   = ( $row->rev_id == $row->page_latest );
 255                                 $this->mTitle     = Title::makeTitle( $row->page_namespace,
 256                                                                       $row->page_title );
 257                         } else {
 258                                 $this->mCurrent = false;
 259                                 $this->mTitle = null;
 260                         }
 261
 262                         if( isset( $row->old_text ) ) {
 263                                 $this->mText  = $this->getRevisionText( $row );
 264                         } else {
 265                                 $this->mText  = null;
 266                         }
 267                 } elseif( is_array( $row ) ) {
 268                         // Build a new revision to be saved...
 269                         global $wgUser;
 270
 271                         $this->mId        = isset( $row['id']         ) ? intval( $row['id']         ) : null;
 272                         $this->mPage      = isset( $row['page']       ) ? intval( $row['page']       ) : null;
 273                         $this->mTextId    = isset( $row['text_id']    ) ? intval( $row['text_id']    ) : null;
 274                         $this->mUserText  = isset( $row['user_text']  ) ? strval( $row['user_text']  ) : $wgUser->getName();
 275                         $this->mUser      = isset( $row['user']       ) ? intval( $row['user']       ) : $wgUser->getId();
 276                         $this->mMinorEdit = isset( $row['minor_edit'] ) ? intval( $row['minor_edit'] ) : 0;
 277                         $this->mTimestamp = isset( $row['timestamp']  ) ? strval( $row['timestamp']  ) : wfTimestamp( TS_MW );
 278                         $this->mDeleted   = isset( $row['deleted']    ) ? intval( $row['deleted']    ) : 0;
 279
 280                         // Enforce spacing trimming on supplied text
 281                         $this->mComment   = isset( $row['comment']    ) ?  trim( strval( $row['comment'] ) ) : null;
 282                         $this->mText      = isset( $row['text']       ) ? rtrim( strval( $row['text']    ) ) : null;
 283
 284                         $this->mTitle     = null; # Load on demand if needed
 285                         $this->mCurrent   = false;
 286                 } else {
 287                         wfDebugDieBacktrace( 'Revision constructor passed invalid row format.' );
 288                 }
 289         }
 290
 291         /**#@+
 292          * @access public
 293          */
 294
 295         /**
 296          * @return int
 297          */
 298         function getId() {
 299                 return $this->mId;
 300         }
 301
 302         /**
 303          * @return int
 304          */
 305         function getTextId() {
 306                 return $this->mTextId;
 307         }
 308
 309         /**
 310          * Returns the title of the page associated with this entry.
 311          * @return Title
 312          */
 313         function getTitle() {
 314                 if( isset( $this->mTitle ) ) {
 315                         return $this->mTitle;
 316                 }
 317                 $dbr =& wfGetDB( DB_SLAVE );
 318                 $row = $dbr->selectRow(
 319                         array( 'page', 'revision' ),
 320                         array( 'page_namespace', 'page_title' ),
 321                         array( 'page_id=rev_page',
 322                                'rev_id' => $this->mId ),
 323                         'Revision::getTItle' );
 324                 if( $row ) {
 325                         $this->mTitle = Title::makeTitle( $row->page_namespace,
 326                                                            $row->page_title );
 327                 }
 328                 return $this->mTitle;
 329         }
 330
 331         /**
 332          * @return int
 333          */
 334         function getPage() {
 335                 return $this->mPage;
 336         }
 337
 338         /**
 339          * Fetch revision's user id if it's available to all users
 340          * @return int
 341          */
 342         function getUser() {
 343                 if( $this->isDeleted( self::MW_REV_DELETED_USER ) ) {
 344                         return 0;
 345                 } else {
 346                         return $this->mUser;
 347                 }
 348         }
 349
 350         /**
 351          * Fetch revision's user id without regard for the current user's permissions
 352          * @return string
 353          */
 354         function getRawUser() {
 355                 return $this->mUser;
 356         }
 357
 358         /**
 359          * Fetch revision's username if it's available to all users
 360          * @return string
 361          */
 362         function getUserText() {
 363                 if( $this->isDeleted( self::MW_REV_DELETED_USER ) ) {
 364                         return "";
 365                 } else {
 366                         return $this->mUserText;
 367                 }
 368         }
 369
 370         /**
 371          * Fetch revision's username without regard for view restrictions
 372          * @return string
 373          */
 374         function getRawUserText() {
 375                 return $this->mUserText;
 376         }
 377
 378         /**
 379          * Fetch revision comment if it's available to all users
 380          * @return string
 381          */
 382         function getComment() {
 383                 if( $this->isDeleted( self::MW_REV_DELETED_COMMENT ) ) {
 384                         return "";
 385                 } else {
 386                         return $this->mComment;
 387                 }
 388         }
 389
 390         /**
 391          * Fetch revision comment without regard for the current user's permissions
 392          * @return string
 393          */
 394         function getRawComment() {
 395                 return $this->mComment;
 396         }
 397
 398         /**
 399          * @return bool
 400          */
 401         function isMinor() {
 402                 return (bool)$this->mMinorEdit;
 403         }
 404
 405         /**
 406          * int $field one of MW_REV_DELETED_* bitfield constants
 407          * @return bool
 408          */
 409         function isDeleted( $field ) {
 410                 return ($this->mDeleted & $field) == $field;
 411         }
 412
 413         /**
 414          * Fetch revision text if it's available to all users
 415          * @return string
 416          */
 417         function getText() {
 418                 if( $this->isDeleted( self::MW_REV_DELETED_TEXT ) ) {
 419                         return "";
 420                 } else {
 421                         return $this->getRawText();
 422                 }
 423         }
 424
 425         /**
 426          * Fetch revision text without regard for view restrictions
 427          * @return string
 428          */
 429         function getRawText() {
 430                 if( is_null( $this->mText ) ) {
 431                         // Revision text is immutable. Load on demand:
 432                         $this->mText = $this->loadText();
 433                 }
 434                 return $this->mText;
 435         }
 436
 437         /**
 438          * @return string
 439          */
 440         function getTimestamp() {
 441                 return wfTimestamp(TS_MW, $this->mTimestamp);
 442         }
 443
 444         /**
 445          * @return bool
 446          */
 447         function isCurrent() {
 448                 return $this->mCurrent;
 449         }
 450
 451         /**
 452          * @return Revision
 453          */
 454         function getPrevious() {
 455                 $prev = $this->mTitle->getPreviousRevisionID( $this->mId );
 456                 if ( $prev ) {
 457                         return Revision::newFromTitle( $this->mTitle, $prev );
 458                 } else {
 459                         return null;
 460                 }
 461         }
 462
 463         /**
 464          * @return Revision
 465          */
 466         function getNext() {
 467                 $next = $this->mTitle->getNextRevisionID( $this->mId );
 468                 if ( $next ) {
 469                         return Revision::newFromTitle( $this->mTitle, $next );
 470                 } else {
 471                         return null;
 472                 }
 473         }
 474         /**#@-*/
 475
 476         /**
 477           * Get revision text associated with an old or archive row
 478           * $row is usually an object from wfFetchRow(), both the flags and the text
 479           * field must be included
 480           * @static
 481           * @param integer $row Id of a row
 482           * @param string $prefix table prefix (default 'old_')
 483           * @return string $text|false the text requested
 484           */
 485         function getRevisionText( $row, $prefix = 'old_' ) {
 486                 $fname = 'Revision::getRevisionText';
 487                 wfProfileIn( $fname );
 488
 489                 # Get data
 490                 $textField = $prefix . 'text';
 491                 $flagsField = $prefix . 'flags';
 492
 493                 if( isset( $row->$flagsField ) ) {
 494                         $flags = explode( ',', $row->$flagsField );
 495                 } else {
 496                         $flags = array();
 497                 }
 498
 499                 if( isset( $row->$textField ) ) {
 500                         $text = $row->$textField;
 501                 } else {
 502                         wfProfileOut( $fname );
 503                         return false;
 504                 }
 505
 506                 # Use external methods for external objects, text in table is URL-only then
 507                 if ( in_array( 'external', $flags ) ) {
 508                         $url=$text;
 509                         @list($proto,$path)=explode('://',$url,2);
 510                         if ($path=="") {
 511                                 wfProfileOut( $fname );
 512                                 return false;
 513                         }
 514                         require_once('ExternalStore.php');
 515                         $text=ExternalStore::fetchFromURL($url);
 516                 }
 517
 518                 // If the text was fetched without an error, convert it
 519                 if ( $text !== false ) {
 520                         if( in_array( 'gzip', $flags ) ) {
 521                                 # Deal with optional compression of archived pages.
 522                                 # This can be done periodically via maintenance/compressOld.php, and
 523                                 # as pages are saved if $wgCompressRevisions is set.
 524                                 $text = gzinflate( $text );
 525                         }
 526
 527                         if( in_array( 'object', $flags ) ) {
 528                                 # Generic compressed storage
 529                                 $obj = unserialize( $text );
 530                                 if ( !is_object( $obj ) ) {
 531                                         // Invalid object
 532                                         wfProfileOut( $fname );
 533                                         return false;
 534                                 }
 535                                 $text = $obj->getText();
 536                         }
 537
 538                         global $wgLegacyEncoding;
 539                         if( $wgLegacyEncoding && !in_array( 'utf-8', $flags ) ) {
 540                                 # Old revisions kept around in a legacy encoding?
 541                                 # Upconvert on demand.
 542                                 global $wgInputEncoding, $wgContLang;
 543                                 $text = $wgContLang->iconv( $wgLegacyEncoding, $wgInputEncoding . '//IGNORE', $text );
 544                         }
 545                 }
 546                 wfProfileOut( $fname );
 547                 return $text;
 548         }
 549
 550         /**
 551          * If $wgCompressRevisions is enabled, we will compress data.
 552          * The input string is modified in place.
 553          * Return value is the flags field: contains 'gzip' if the
 554          * data is compressed, and 'utf-8' if we're saving in UTF-8
 555          * mode.
 556          *
 557          * @static
 558          * @param mixed $text reference to a text
 559          * @return string
 560          */
 561         function compressRevisionText( &$text ) {
 562                 global $wgCompressRevisions;
 563                 $flags = array();
 564
 565                 # Revisions not marked this way will be converted
 566                 # on load if $wgLegacyCharset is set in the future.
 567                 $flags[] = 'utf-8';
 568
 569                 if( $wgCompressRevisions ) {
 570                         if( function_exists( 'gzdeflate' ) ) {
 571                                 $text = gzdeflate( $text );
 572                                 $flags[] = 'gzip';
 573                         } else {
 574                                 wfDebug( "Revision::compressRevisionText() -- no zlib support, not compressing\n" );
 575                         }
 576                 }
 577                 return implode( ',', $flags );
 578         }
 579
 580         /**
 581          * Insert a new revision into the database, returning the new revision ID
 582          * number on success and dies horribly on failure.
 583          *
 584          * @param Database $dbw
 585          * @return int
 586          */
 587         function insertOn( &$dbw ) {
 588                 global $wgDefaultExternalStore;
 589
 590                 $fname = 'Revision::insertOn';
 591                 wfProfileIn( $fname );
 592
 593                 $data = $this->mText;
 594                 $flags = Revision::compressRevisionText( $data );
 595
 596                 # Write to external storage if required
 597                 if ( $wgDefaultExternalStore ) {
 598                         if ( is_array( $wgDefaultExternalStore ) ) {
 599                                 // Distribute storage across multiple clusters
 600                                 $store = $wgDefaultExternalStore[mt_rand(0, count( $wgDefaultExternalStore ) - 1)];
 601                         } else {
 602                                 $store = $wgDefaultExternalStore;
 603                         }
 604                         require_once('ExternalStore.php');
 605                         // Store and get the URL
 606                         $data = ExternalStore::insert( $store, $data );
 607                         if ( !$data ) {
 608                                 # This should only happen in the case of a configuration error, where the external store is not valid
 609                                 wfDebugDieBacktrace( "Unable to store text to external storage $store" );
 610                         }
 611                         if ( $flags ) {
 612                                 $flags .= ',';
 613                         }
 614                         $flags .= 'external';
 615                 }
 616
 617                 # Record the text (or external storage URL) to the text table
 618                 if( !isset( $this->mTextId ) ) {
 619                         $old_id = $dbw->nextSequenceValue( 'text_old_id_val' );
 620                         $dbw->insert( 'text',
 621                                 array(
 622                                         'old_id'    => $old_id,
 623                                         'old_text'  => $data,
 624                                         'old_flags' => $flags,
 625                                 ), $fname
 626                         );
 627                         $this->mTextId = $dbw->insertId();
 628                 }
 629
 630                 # Record the edit in revisions
 631                 $rev_id = isset( $this->mId )
 632                         ? $this->mId
 633                         : $dbw->nextSequenceValue( 'rev_rev_id_val' );
 634                 $dbw->insert( 'revision',
 635                         array(
 636                                 'rev_id'         => $rev_id,
 637                                 'rev_page'       => $this->mPage,
 638                                 'rev_text_id'    => $this->mTextId,
 639                                 'rev_comment'    => $this->mComment,
 640                                 'rev_minor_edit' => $this->mMinorEdit ? 1 : 0,
 641                                 'rev_user'       => $this->mUser,
 642                                 'rev_user_text'  => $this->mUserText,
 643                                 'rev_timestamp'  => $dbw->timestamp( $this->mTimestamp ),
 644                                 'rev_deleted'    => $this->mDeleted,
 645                         ), $fname
 646                 );
 647
 648                 $this->mId = !is_null($rev_id) ? $rev_id : $dbw->insertId();
 649                 wfProfileOut( $fname );
 650                 return $this->mId;
 651         }
 652
 653         /**
 654          * Lazy-load the revision's text.
 655          * Currently hardcoded to the 'text' table storage engine.
 656          *
 657          * @return string
 658          * @access private
 659          */
 660         function loadText() {
 661                 $fname = 'Revision::loadText';
 662                 wfProfileIn( $fname );
 663
 664                 $dbr =& wfGetDB( DB_SLAVE );
 665                 $row = $dbr->selectRow( 'text',
 666                         array( 'old_text', 'old_flags' ),
 667                         array( 'old_id' => $this->getTextId() ),
 668                         $fname);
 669
 670                 if( !$row ) {
 671                         $dbw =& wfGetDB( DB_MASTER );
 672                         $row = $dbw->selectRow( 'text',
 673                                 array( 'old_text', 'old_flags' ),
 674                                 array( 'old_id' => $this->getTextId() ),
 675                                 $fname);
 676                 }
 677
 678                 $text = Revision::getRevisionText( $row );
 679                 wfProfileOut( $fname );
 680
 681                 return $text;
 682         }
 683
 684         /**
 685          * Create a new null-revision for insertion into a page's
 686          * history. This will not re-save the text, but simply refer
 687          * to the text from the previous version.
 688          *
 689          * Such revisions can for instance identify page rename
 690          * operations and other such meta-modifications.
 691          *
 692          * @param Database $dbw
 693          * @param int      $pageId ID number of the page to read from
 694          * @param string   $summary
 695          * @param bool     $minor
 696          * @return Revision
 697          */
 698         function newNullRevision( &$dbw, $pageId, $summary, $minor ) {
 699                 $fname = 'Revision::newNullRevision';
 700                 wfProfileIn( $fname );
 701
 702                 $current = $dbw->selectRow(
 703                         array( 'page', 'revision' ),
 704                         array( 'page_latest', 'rev_text_id' ),
 705                         array(
 706                                 'page_id' => $pageId,
 707                                 'page_latest=rev_id',
 708                                 ),
 709                         $fname );
 710
 711                 if( $current ) {
 712                         $revision = new Revision( array(
 713                                 'page'       => $pageId,
 714                                 'comment'    => $summary,
 715                                 'minor_edit' => $minor,
 716                                 'text_id'    => $current->rev_text_id,
 717                                 ) );
 718                 } else {
 719                         $revision = null;
 720                 }
 721
 722                 wfProfileOut( $fname );
 723                 return $revision;
 724         }
 725
 726         /**
 727          * Determine if the current user is allowed to view a particular
 728          * field of this revision, if it's marked as deleted.
 729          * @param int $field one of self::MW_REV_DELETED_TEXT,
 730          *                          self::MW_REV_DELETED_COMMENT,
 731          *                          self::MW_REV_DELETED_USER
 732          * @return bool
 733          */
 734         function userCan( $field ) {
 735                 if( ( $this->mDeleted & $field ) == $field ) {
 736                         global $wgUser;
 737                         $permission = ( $this->mDeleted & self::MW_REV_DELETED_RESTRICTED ) == self::MW_REV_DELETED_RESTRICTED
 738                                 ? 'hiderevision'
 739                                 : 'deleterevision';
 740                         wfDebug( "Checking for $permission due to $field match on $this->mDeleted\n" );
 741                         return $wgUser->isAllowed( $permission );
 742                 } else {
 743                         return true;
 744                 }
 745         }
 746
 747 }
 748
 749 ?>