includes/Database.php

   1 <?php
   2 /**
   3  * This file deals with MySQL interface functions
   4  * and query specifics/optimisations
   5  */
   6
   7 /** Number of times to re-try an operation in case of deadlock */
   8 define( 'DEADLOCK_TRIES', 4 );
   9 /** Minimum time to wait before retry, in microseconds */
  10 define( 'DEADLOCK_DELAY_MIN', 500000 );
  11 /** Maximum time to wait before retry */
  12 define( 'DEADLOCK_DELAY_MAX', 1500000 );
  13
  14 /******************************************************************************
  15  * Utility classes
  16  *****************************************************************************/
  17
  18 class DBObject {
  19         public $mData;
  20
  21         function DBObject($data) {
  22                 $this->mData = $data;
  23         }
  24
  25         function isLOB() {
  26                 return false;
  27         }
  28
  29         function data() {
  30                 return $this->mData;
  31         }
  32 };
  33
  34 class MySQLField {
  35         private $name, $tablename, $default, $max_length, $nullable,
  36                 $is_pk, $is_unique, $is_key, $type;
  37         function __construct ($info) {
  38                 $this->name = $info->name;
  39                 $this->tablename = $info->table;
  40                 $this->default = $info->def;
  41                 $this->max_length = $info->max_length;
  42                 $this->nullable = !$info->not_null;
  43                 $this->is_pk = $info->primary_key;
  44                 $this->is_unique = $info->unique_key;
  45                 $this->is_multiple = $info->multiple_key;
  46                 $this->is_key = ($this->is_pk || $this->is_unique || $this->is_multiple);
  47                 $this->type = $info->type;
  48         }
  49
  50         function name() {
  51                 return $this->name;
  52         }
  53
  54         function tableName() {
  55                 return $this->tableName;
  56         }
  57
  58         function defaultValue() {
  59                 return $this->default;
  60         }
  61
  62         function maxLength() {
  63                 return $this->max_length;
  64         }
  65
  66         function nullable() {
  67                 return $this->nullable;
  68         }
  69
  70         function isKey() {
  71                 return $this->is_key;
  72         }
  73
  74         function isMultipleKey() {
  75                 return $this->is_multiple;
  76         }
  77
  78         function type() {
  79                 return $this->type;
  80         }
  81 }
  82
  83 /******************************************************************************
  84  * Error classes
  85  *****************************************************************************/
  86
  87 /**
  88  * Database error base class
  89  */
  90 class DBError extends MWException {
  91         public $db;
  92
  93         /**
  94          * Construct a database error
  95          * @param Database $db The database object which threw the error
  96          * @param string $error A simple error message to be used for debugging
  97          */
  98         function __construct( Database &$db, $error ) {
  99                 $this->db =& $db;
 100                 parent::__construct( $error );
 101         }
 102 }
 103
 104 class DBConnectionError extends DBError {
 105         public $error;
 106
 107         function __construct( Database &$db, $error = 'unknown error' ) {
 108                 $msg = 'DB connection error';
 109                 if ( trim( $error ) != '' ) {
 110                         $msg .= ": $error";
 111                 }
 112                 $this->error = $error;
 113                 parent::__construct( $db, $msg );
 114         }
 115
 116         function useOutputPage() {
 117                 // Not likely to work
 118                 return false;
 119         }
 120
 121         function useMessageCache() {
 122                 // Not likely to work
 123                 return false;
 124         }
 125
 126         function getText() {
 127                 return $this->getMessage() . "\n";
 128         }
 129
 130         function getLogMessage() {
 131                 # Don't send to the exception log
 132                 return false;
 133         }
 134
 135         function getPageTitle() {
 136                 global $wgSitename;
 137                 return "$wgSitename has a problem";
 138         }
 139
 140         function getHTML() {
 141                 global $wgTitle, $wgUseFileCache, $title, $wgInputEncoding;
 142                 global $wgSitename, $wgServer, $wgMessageCache;
 143
 144                 # I give up, Brion is right. Getting the message cache to work when there is no DB is tricky.
 145                 # Hard coding strings instead.
 146
 147                 $noconnect = "<p><strong>Sorry! This site is experiencing technical difficulties.</strong></p><p>Try waiting a few minutes and reloading.</p><p><small>(Can't contact the database server: $1)</small></p>";
 148                 $mainpage = 'Main Page';
 149                 $searchdisabled = <<<EOT
 150 <p style="margin: 1.5em 2em 1em">$wgSitename search is disabled for performance reasons. You can search via Google in the meantime.
 151 <span style="font-size: 89%; display: block; margin-left: .2em">Note that their indexes of $wgSitename content may be out of date.</span></p>',
 152 EOT;
 153
 154                 $googlesearch = "
 155 <!-- SiteSearch Google -->
 156 <FORM method=GET action=\"http://www.google.com/search\">
 157 <TABLE bgcolor=\"#FFFFFF\"><tr><td>
 158 <A HREF=\"http://www.google.com/\">
 159 <IMG SRC=\"http://www.google.com/logos/Logo_40wht.gif\"
 160 border=\"0\" ALT=\"Google\"></A>
 161 </td>
 162 <td>
 163 <INPUT TYPE=text name=q size=31 maxlength=255 value=\"$1\">
 164 <INPUT type=submit name=btnG VALUE=\"Google Search\">
 165 <font size=-1>
 166 <input type=hidden name=domains value=\"$wgServer\"><br /><input type=radio name=sitesearch value=\"\"> WWW <input type=radio name=sitesearch value=\"$wgServer\" checked> $wgServer <br />
 167 <input type='hidden' name='ie' value='$2'>
 168 <input type='hidden' name='oe' value='$2'>
 169 </font>
 170 </td></tr></TABLE>
 171 </FORM>
 172 <!-- SiteSearch Google -->";
 173                 $cachederror = "The following is a cached copy of the requested page, and may not be up to date. ";
 174
 175                 # No database access
 176                 if ( is_object( $wgMessageCache ) ) {
 177                         $wgMessageCache->disable();
 178                 }
 179
 180                 if ( trim( $this->error ) == '' ) {
 181                         $this->error = $this->db->getProperty('mServer');
 182                 }
 183
 184                 $text = str_replace( '$1', $this->error, $noconnect );
 185                 $text .= wfGetSiteNotice();
 186
 187                 if($wgUseFileCache) {
 188                         if($wgTitle) {
 189                                 $t =& $wgTitle;
 190                         } else {
 191                                 if($title) {
 192                                         $t = Title::newFromURL( $title );
 193                                 } elseif (@/**/$_REQUEST['search']) {
 194                                         $search = $_REQUEST['search'];
 195                                         return $searchdisabled .
 196                                           str_replace( array( '$1', '$2' ), array( htmlspecialchars( $search ),
 197                                           $wgInputEncoding ), $googlesearch );
 198                                 } else {
 199                                         $t = Title::newFromText( $mainpage );
 200                                 }
 201                         }
 202
 203                         $cache = new HTMLFileCache( $t );
 204                         if( $cache->isFileCached() ) {
 205                                 // FIXME: $msg is not defined on the next line.
 206                                 $msg = '<p style="color: red"><b>'.$msg."<br />\n" .
 207                                         $cachederror . "</b></p>\n";
 208
 209                                 $tag = '<div id="article">';
 210                                 $text = str_replace(
 211                                         $tag,
 212                                         $tag . $msg,
 213                                         $cache->fetchPageText() );
 214                         }
 215                 }
 216
 217                 return $text;
 218         }
 219 }
 220
 221 class DBQueryError extends DBError {
 222         public $error, $errno, $sql, $fname;
 223
 224         function __construct( Database &$db, $error, $errno, $sql, $fname ) {
 225                 $message = "A database error has occurred\n" .
 226                   "Query: $sql\n" .
 227                   "Function: $fname\n" .
 228                   "Error: $errno $error\n";
 229
 230                 parent::__construct( $db, $message );
 231                 $this->error = $error;
 232                 $this->errno = $errno;
 233                 $this->sql = $sql;
 234                 $this->fname = $fname;
 235         }
 236
 237         function getText() {
 238                 if ( $this->useMessageCache() ) {
 239                         return wfMsg( 'dberrortextcl', htmlspecialchars( $this->getSQL() ),
 240                           htmlspecialchars( $this->fname ), $this->errno, htmlspecialchars( $this->error ) ) . "\n";
 241                 } else {
 242                         return $this->getMessage();
 243                 }
 244         }
 245
 246         function getSQL() {
 247                 global $wgShowSQLErrors;
 248                 if( !$wgShowSQLErrors ) {
 249                         return $this->msg( 'sqlhidden', 'SQL hidden' );
 250                 } else {
 251                         return $this->sql;
 252                 }
 253         }
 254
 255         function getLogMessage() {
 256                 # Don't send to the exception log
 257                 return false;
 258         }
 259
 260         function getPageTitle() {
 261                 return $this->msg( 'databaseerror', 'Database error' );
 262         }
 263
 264         function getHTML() {
 265                 if ( $this->useMessageCache() ) {
 266                         return wfMsgNoDB( 'dberrortext', htmlspecialchars( $this->getSQL() ),
 267                           htmlspecialchars( $this->fname ), $this->errno, htmlspecialchars( $this->error ) );
 268                 } else {
 269                         return nl2br( htmlspecialchars( $this->getMessage() ) );
 270                 }
 271         }
 272 }
 273
 274 class DBUnexpectedError extends DBError {}
 275
 276 /******************************************************************************/
 277
 278 /**
 279  * Database abstraction object
 280  */
 281 class Database {
 282
 283 #------------------------------------------------------------------------------
 284 # Variables
 285 #------------------------------------------------------------------------------
 286
 287         protected $mLastQuery = '';
 288
 289         protected $mServer, $mUser, $mPassword, $mConn = null, $mDBname;
 290         protected $mOut, $mOpened = false;
 291
 292         protected $mFailFunction;
 293         protected $mTablePrefix;
 294         protected $mFlags;
 295         protected $mTrxLevel = 0;
 296         protected $mErrorCount = 0;
 297         protected $mLBInfo = array();
 298
 299 #------------------------------------------------------------------------------
 300 # Accessors
 301 #------------------------------------------------------------------------------
 302         # These optionally set a variable and return the previous state
 303
 304         /**
 305          * Fail function, takes a Database as a parameter
 306          * Set to false for default, 1 for ignore errors
 307          */
 308         function failFunction( $function = NULL ) {
 309                 return wfSetVar( $this->mFailFunction, $function );
 310         }
 311
 312         /**
 313          * Output page, used for reporting errors
 314          * FALSE means discard output
 315          */
 316         function setOutputPage( $out ) {
 317                 $this->mOut = $out;
 318         }
 319
 320         /**
 321          * Boolean, controls output of large amounts of debug information
 322          */
 323         function debug( $debug = NULL ) {
 324                 return wfSetBit( $this->mFlags, DBO_DEBUG, $debug );
 325         }
 326
 327         /**
 328          * Turns buffering of SQL result sets on (true) or off (false).
 329          * Default is "on" and it should not be changed without good reasons.
 330          */
 331         function bufferResults( $buffer = NULL ) {
 332                 if ( is_null( $buffer ) ) {
 333                         return !(bool)( $this->mFlags & DBO_NOBUFFER );
 334                 } else {
 335                         return !wfSetBit( $this->mFlags, DBO_NOBUFFER, !$buffer );
 336                 }
 337         }
 338
 339         /**
 340          * Turns on (false) or off (true) the automatic generation and sending
 341          * of a "we're sorry, but there has been a database error" page on
 342          * database errors. Default is on (false). When turned off, the
 343          * code should use lastErrno() and lastError() to handle the
 344          * situation as appropriate.
 345          */
 346         function ignoreErrors( $ignoreErrors = NULL ) {
 347                 return wfSetBit( $this->mFlags, DBO_IGNORE, $ignoreErrors );
 348         }
 349
 350         /**
 351          * The current depth of nested transactions
 352          * @param $level Integer: , default NULL.
 353          */
 354         function trxLevel( $level = NULL ) {
 355                 return wfSetVar( $this->mTrxLevel, $level );
 356         }
 357
 358         /**
 359          * Number of errors logged, only useful when errors are ignored
 360          */
 361         function errorCount( $count = NULL ) {
 362                 return wfSetVar( $this->mErrorCount, $count );
 363         }
 364
 365         /**
 366          * Properties passed down from the server info array of the load balancer
 367          */
 368         function getLBInfo( $name = NULL ) {
 369                 if ( is_null( $name ) ) {
 370                         return $this->mLBInfo;
 371                 } else {
 372                         if ( array_key_exists( $name, $this->mLBInfo ) ) {
 373                                 return $this->mLBInfo[$name];
 374                         } else {
 375                                 return NULL;
 376                         }
 377                 }
 378         }
 379
 380         function setLBInfo( $name, $value = NULL ) {
 381                 if ( is_null( $value ) ) {
 382                         $this->mLBInfo = $name;
 383                 } else {
 384                         $this->mLBInfo[$name] = $value;
 385                 }
 386         }
 387
 388         /**
 389          * Returns true if this database supports (and uses) cascading deletes
 390          */
 391         function cascadingDeletes() {
 392                 return false;
 393         }
 394
 395         /**
 396          * Returns true if this database supports (and uses) triggers (e.g. on the page table)
 397          */
 398         function cleanupTriggers() {
 399                 return false;
 400         }
 401
 402         /**
 403          * Returns true if this database is strict about what can be put into an IP field.
 404          * Specifically, it uses a NULL value instead of an empty string.
 405          */
 406         function strictIPs() {
 407                 return false;
 408         }
 409
 410         /**
 411          * Returns true if this database uses timestamps rather than integers
 412         */
 413         function realTimestamps() {
 414                 return false;
 415         }
 416
 417         /**
 418          * Returns true if this database does an implicit sort when doing GROUP BY
 419          */
 420         function implicitGroupby() {
 421                 return true;
 422         }
 423
 424         /**
 425          * Returns true if this database can do a native search on IP columns
 426          * e.g. this works as expected: .. WHERE rc_ip = '127.42.12.102/32';
 427          */
 428         function searchableIPs() {
 429                 return false;
 430         }
 431
 432         /**#@+
 433          * Get function
 434          */
 435         function lastQuery() { return $this->mLastQuery; }
 436         function isOpen() { return $this->mOpened; }
 437         /**#@-*/
 438
 439         function setFlag( $flag ) {
 440                 $this->mFlags |= $flag;
 441         }
 442
 443         function clearFlag( $flag ) {
 444                 $this->mFlags &= ~$flag;
 445         }
 446
 447         function getFlag( $flag ) {
 448                 return !!($this->mFlags & $flag);
 449         }
 450
 451         /**
 452          * General read-only accessor
 453          */
 454         function getProperty( $name ) {
 455                 return $this->$name;
 456         }
 457
 458 #------------------------------------------------------------------------------
 459 # Other functions
 460 #------------------------------------------------------------------------------
 461
 462         /**@{{
 463          * @param string $server database server host
 464          * @param string $user database user name
 465          * @param string $password database user password
 466          * @param string $dbname database name
 467          */
 468
 469         /**
 470          * @param failFunction
 471          * @param $flags
 472          * @param $tablePrefix String: database table prefixes. By default use the prefix gave in LocalSettings.php
 473          */
 474         function __construct( $server = false, $user = false, $password = false, $dbName = false,
 475                 $failFunction = false, $flags = 0, $tablePrefix = 'get from global' ) {
 476
 477                 global $wgOut, $wgDBprefix, $wgCommandLineMode;
 478                 # Can't get a reference if it hasn't been set yet
 479                 if ( !isset( $wgOut ) ) {
 480                         $wgOut = NULL;
 481                 }
 482                 $this->mOut =& $wgOut;
 483
 484                 $this->mFailFunction = $failFunction;
 485                 $this->mFlags = $flags;
 486
 487                 if ( $this->mFlags & DBO_DEFAULT ) {
 488                         if ( $wgCommandLineMode ) {
 489                                 $this->mFlags &= ~DBO_TRX;
 490                         } else {
 491                                 $this->mFlags |= DBO_TRX;
 492                         }
 493                 }
 494
 495                 /*
 496                 // Faster read-only access
 497                 if ( wfReadOnly() ) {
 498                         $this->mFlags |= DBO_PERSISTENT;
 499                         $this->mFlags &= ~DBO_TRX;
 500                 }*/
 501
 502                 /** Get the default table prefix*/
 503                 if ( $tablePrefix == 'get from global' ) {
 504                         $this->mTablePrefix = $wgDBprefix;
 505                 } else {
 506                         $this->mTablePrefix = $tablePrefix;
 507                 }
 508
 509                 if ( $server ) {
 510                         $this->open( $server, $user, $password, $dbName );
 511                 }
 512         }
 513
 514         /**
 515          * @static
 516          * @param failFunction
 517          * @param $flags
 518          */
 519         static function newFromParams( $server, $user, $password, $dbName, $failFunction = false, $flags = 0 )
 520         {
 521                 return new Database( $server, $user, $password, $dbName, $failFunction, $flags );
 522         }
 523
 524         /**
 525          * Usually aborts on failure
 526          * If the failFunction is set to a non-zero integer, returns success
 527          */
 528         function open( $server, $user, $password, $dbName ) {
 529                 global $wguname;
 530                 wfProfileIn( __METHOD__ );
 531
 532                 # Test for missing mysql.so
 533                 # First try to load it
 534                 if (!@extension_loaded('mysql')) {
 535                         @dl('mysql.so');
 536                 }
 537
 538                 # Fail now
 539                 # Otherwise we get a suppressed fatal error, which is very hard to track down
 540                 if ( !function_exists( 'mysql_connect' ) ) {
 541                         throw new DBConnectionError( $this, "MySQL functions missing, have you compiled PHP with the --with-mysql option?\n" );
 542                 }
 543
 544                 $this->close();
 545                 $this->mServer = $server;
 546                 $this->mUser = $user;
 547                 $this->mPassword = $password;
 548                 $this->mDBname = $dbName;
 549
 550                 $success = false;
 551
 552                 wfProfileIn("dbconnect-$server");
 553
 554                 # LIVE PATCH by Tim, ask Domas for why: retry loop
 555                 $this->mConn = false;
 556                 $max = 3;
 557                 for ( $i = 0; $i < $max && !$this->mConn; $i++ ) {
 558                         if ( $i > 1 ) {
 559                                 usleep( 1000 );
 560                         }
 561                         if ( $this->mFlags & DBO_PERSISTENT ) {
 562                                 @/**/$this->mConn = mysql_pconnect( $server, $user, $password );
 563                         } else {
 564                                 # Create a new connection...
 565                                 @/**/$this->mConn = mysql_connect( $server, $user, $password, true );
 566                         }
 567                         if ($this->mConn === false) {
 568                                 $iplus = $i + 1;
 569                                 #wfLogDBError("Connect loop error $iplus of $max ($server): " . mysql_errno() . " - " . mysql_error()."\n");
 570                         }
 571                 }
 572
 573                 wfProfileOut("dbconnect-$server");
 574
 575                 if ( $dbName != '' ) {
 576                         if ( $this->mConn !== false ) {
 577                                 $success = @/**/mysql_select_db( $dbName, $this->mConn );
 578                                 if ( !$success ) {
 579                                         $error = "Error selecting database $dbName on server {$this->mServer} " .
 580                                                 "from client host {$wguname['nodename']}\n";
 581                                         wfLogDBError(" Error selecting database $dbName on server {$this->mServer} \n");
 582                                         wfDebug( $error );
 583                                 }
 584                         } else {
 585                                 wfDebug( "DB connection error\n" );
 586                                 wfDebug( "Server: $server, User: $user, Password: " .
 587                                         substr( $password, 0, 3 ) . "..., error: " . mysql_error() . "\n" );
 588                                 $success = false;
 589                         }
 590                 } else {
 591                         # Delay USE query
 592                         $success = (bool)$this->mConn;
 593                 }
 594
 595                 if ( $success ) {
 596                         global $wgDBmysql5;
 597                         if( $wgDBmysql5 ) {
 598                                 // Tell the server we're communicating with it in UTF-8.
 599                                 // This may engage various charset conversions.
 600                                 $this->query( 'SET NAMES utf8' );
 601                         }
 602                 } else {
 603                         $this->reportConnectionError();
 604                 }
 605
 606                 $this->mOpened = $success;
 607                 wfProfileOut( __METHOD__ );
 608                 return $success;
 609         }
 610         /**@}}*/
 611
 612         /**
 613          * Closes a database connection.
 614          * if it is open : commits any open transactions
 615          *
 616          * @return bool operation success. true if already closed.
 617          */
 618         function close()
 619         {
 620                 $this->mOpened = false;
 621                 if ( $this->mConn ) {
 622                         if ( $this->trxLevel() ) {
 623                                 $this->immediateCommit();
 624                         }
 625                         return mysql_close( $this->mConn );
 626                 } else {
 627                         return true;
 628                 }
 629         }
 630
 631         /**
 632          * @param string $error fallback error message, used if none is given by MySQL
 633          */
 634         function reportConnectionError( $error = 'Unknown error' ) {
 635                 $myError = $this->lastError();
 636                 if ( $myError ) {
 637                         $error = $myError;
 638                 }
 639
 640                 if ( $this->mFailFunction ) {
 641                         # Legacy error handling method
 642                         if ( !is_int( $this->mFailFunction ) ) {
 643                                 $ff = $this->mFailFunction;
 644                                 $ff( $this, $error );
 645                         }
 646                 } else {
 647                         # New method
 648                         wfLogDBError( "Connection error: $error\n" );
 649                         throw new DBConnectionError( $this, $error );
 650                 }
 651         }
 652
 653         /**
 654          * Usually aborts on failure
 655          * If errors are explicitly ignored, returns success
 656          */
 657         function query( $sql, $fname = '', $tempIgnore = false ) {
 658                 global $wgProfiling;
 659
 660                 if ( $wgProfiling ) {
 661                         # generalizeSQL will probably cut down the query to reasonable
 662                         # logging size most of the time. The substr is really just a sanity check.
 663
 664                         # Who's been wasting my precious column space? -- TS
 665                         #$profName = 'query: ' . $fname . ' ' . substr( Database::generalizeSQL( $sql ), 0, 255 );
 666
 667                         if ( is_null( $this->getLBInfo( 'master' ) ) ) {
 668                                 $queryProf = 'query: ' . substr( Database::generalizeSQL( $sql ), 0, 255 );
 669                                 $totalProf = 'Database::query';
 670                         } else {
 671                                 $queryProf = 'query-m: ' . substr( Database::generalizeSQL( $sql ), 0, 255 );
 672                                 $totalProf = 'Database::query-master';
 673                         }
 674                         wfProfileIn( $totalProf );
 675                         wfProfileIn( $queryProf );
 676                 }
 677
 678                 $this->mLastQuery = $sql;
 679
 680                 # Add a comment for easy SHOW PROCESSLIST interpretation
 681                 if ( $fname ) {
 682                         $commentedSql = preg_replace('/\s/', " /* $fname */ ", $sql, 1);
 683                 } else {
 684                         $commentedSql = $sql;
 685                 }
 686
 687                 # If DBO_TRX is set, start a transaction
 688                 if ( ( $this->mFlags & DBO_TRX ) && !$this->trxLevel() &&
 689                         $sql != 'BEGIN' && $sql != 'COMMIT' && $sql != 'ROLLBACK'
 690                 ) {
 691                         $this->begin();
 692                 }
 693
 694                 if ( $this->debug() ) {
 695                         $sqlx = substr( $commentedSql, 0, 500 );
 696                         $sqlx = strtr( $sqlx, "\t\n", '  ' );
 697                         wfDebug( "SQL: $sqlx\n" );
 698                 }
 699
 700                 # Do the query and handle errors
 701                 $ret = $this->doQuery( $commentedSql );
 702
 703                 # Try reconnecting if the connection was lost
 704                 if ( false === $ret && ( $this->lastErrno() == 2013 || $this->lastErrno() == 2006 ) ) {
 705                         # Transaction is gone, like it or not
 706                         $this->mTrxLevel = 0;
 707                         wfDebug( "Connection lost, reconnecting...\n" );
 708                         if ( $this->ping() ) {
 709                                 wfDebug( "Reconnected\n" );
 710                                 $sqlx = substr( $commentedSql, 0, 500 );
 711                                 $sqlx = strtr( $sqlx, "\t\n", '  ' );
 712                                 global $wgRequestTime;
 713                                 $elapsed = round( microtime(true) - $wgRequestTime, 3 );
 714                                 wfLogDBError( "Connection lost and reconnected after {$elapsed}s, query: $sqlx\n" );
 715                                 $ret = $this->doQuery( $commentedSql );
 716                         } else {
 717                                 wfDebug( "Failed\n" );
 718                         }
 719                 }
 720
 721                 if ( false === $ret ) {
 722                         $this->reportQueryError( $this->lastError(), $this->lastErrno(), $sql, $fname, $tempIgnore );
 723                 }
 724
 725                 if ( $wgProfiling ) {
 726                         wfProfileOut( $queryProf );
 727                         wfProfileOut( $totalProf );
 728                 }
 729                 return $ret;
 730         }
 731
 732         /**
 733          * The DBMS-dependent part of query()
 734          * @param string $sql SQL query.
 735          */
 736         function doQuery( $sql ) {
 737                 if( $this->bufferResults() ) {
 738                         $ret = mysql_query( $sql, $this->mConn );
 739                 } else {
 740                         $ret = mysql_unbuffered_query( $sql, $this->mConn );
 741                 }
 742                 return $ret;
 743         }
 744
 745         /**
 746          * @param $error
 747          * @param $errno
 748          * @param $sql
 749          * @param string $fname
 750          * @param bool $tempIgnore
 751          */
 752         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 753                 global $wgCommandLineMode;
 754                 # Ignore errors during error handling to avoid infinite recursion
 755                 $ignore = $this->ignoreErrors( true );
 756                 ++$this->mErrorCount;
 757
 758                 if( $ignore || $tempIgnore ) {
 759                         wfDebug("SQL ERROR (ignored): $error\n");
 760                         $this->ignoreErrors( $ignore );
 761                 } else {
 762                         $sql1line = str_replace( "\n", "\\n", $sql );
 763                         wfLogDBError("$fname\t{$this->mServer}\t$errno\t$error\t$sql1line\n");
 764                         wfDebug("SQL ERROR: " . $error . "\n");
 765                         throw new DBQueryError( $this, $error, $errno, $sql, $fname );
 766                 }
 767         }
 768
 769
 770         /**
 771          * Intended to be compatible with the PEAR::DB wrapper functions.
 772          * http://pear.php.net/manual/en/package.database.db.intro-execute.php
 773          *
 774          * ? = scalar value, quoted as necessary
 775          * ! = raw SQL bit (a function for instance)
 776          * & = filename; reads the file and inserts as a blob
 777          *     (we don't use this though...)
 778          */
 779         function prepare( $sql, $func = 'Database::prepare' ) {
 780                 /* MySQL doesn't support prepared statements (yet), so just
 781                    pack up the query for reference. We'll manually replace
 782                    the bits later. */
 783                 return array( 'query' => $sql, 'func' => $func );
 784         }
 785
 786         function freePrepared( $prepared ) {
 787                 /* No-op for MySQL */
 788         }
 789
 790         /**
 791          * Execute a prepared query with the various arguments
 792          * @param string $prepared the prepared sql
 793          * @param mixed $args Either an array here, or put scalars as varargs
 794          */
 795         function execute( $prepared, $args = null ) {
 796                 if( !is_array( $args ) ) {
 797                         # Pull the var args
 798                         $args = func_get_args();
 799                         array_shift( $args );
 800                 }
 801                 $sql = $this->fillPrepared( $prepared['query'], $args );
 802                 return $this->query( $sql, $prepared['func'] );
 803         }
 804
 805         /**
 806          * Prepare & execute an SQL statement, quoting and inserting arguments
 807          * in the appropriate places.
 808          * @param string $query
 809          * @param string $args ...
 810          */
 811         function safeQuery( $query, $args = null ) {
 812                 $prepared = $this->prepare( $query, 'Database::safeQuery' );
 813                 if( !is_array( $args ) ) {
 814                         # Pull the var args
 815                         $args = func_get_args();
 816                         array_shift( $args );
 817                 }
 818                 $retval = $this->execute( $prepared, $args );
 819                 $this->freePrepared( $prepared );
 820                 return $retval;
 821         }
 822
 823         /**
 824          * For faking prepared SQL statements on DBs that don't support
 825          * it directly.
 826          * @param string $preparedSql - a 'preparable' SQL statement
 827          * @param array $args - array of arguments to fill it with
 828          * @return string executable SQL
 829          */
 830         function fillPrepared( $preparedQuery, $args ) {
 831                 reset( $args );
 832                 $this->preparedArgs =& $args;
 833                 return preg_replace_callback( '/(\\\\[?!&]|[?!&])/',
 834                         array( &$this, 'fillPreparedArg' ), $preparedQuery );
 835         }
 836
 837         /**
 838          * preg_callback func for fillPrepared()
 839          * The arguments should be in $this->preparedArgs and must not be touched
 840          * while we're doing this.
 841          *
 842          * @param array $matches
 843          * @return string
 844          * @private
 845          */
 846         function fillPreparedArg( $matches ) {
 847                 switch( $matches[1] ) {
 848                         case '\\?': return '?';
 849                         case '\\!': return '!';
 850                         case '\\&': return '&';
 851                 }
 852                 list( /* $n */ , $arg ) = each( $this->preparedArgs );
 853                 switch( $matches[1] ) {
 854                         case '?': return $this->addQuotes( $arg );
 855                         case '!': return $arg;
 856                         case '&':
 857                                 # return $this->addQuotes( file_get_contents( $arg ) );
 858                                 throw new DBUnexpectedError( $this, '& mode is not implemented. If it\'s really needed, uncomment the line above.' );
 859                         default:
 860                                 throw new DBUnexpectedError( $this, 'Received invalid match. This should never happen!' );
 861                 }
 862         }
 863
 864         /**#@+
 865          * @param mixed $res A SQL result
 866          */
 867         /**
 868          * Free a result object
 869          */
 870         function freeResult( $res ) {
 871                 if ( !@/**/mysql_free_result( $res ) ) {
 872                         throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
 873                 }
 874         }
 875
 876         /**
 877          * Fetch the next row from the given result object, in object form
 878          */
 879         function fetchObject( $res ) {
 880                 @/**/$row = mysql_fetch_object( $res );
 881                 if( $this->lastErrno() ) {
 882                         throw new DBUnexpectedError( $this, 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() ) );
 883                 }
 884                 return $row;
 885         }
 886
 887         /**
 888          * Fetch the next row from the given result object
 889          * Returns an array
 890          */
 891         function fetchRow( $res ) {
 892                 @/**/$row = mysql_fetch_array( $res );
 893                 if ( $this->lastErrno() ) {
 894                         throw new DBUnexpectedError( $this, 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() ) );
 895                 }
 896                 return $row;
 897         }
 898
 899         /**
 900          * Get the number of rows in a result object
 901          */
 902         function numRows( $res ) {
 903                 @/**/$n = mysql_num_rows( $res );
 904                 if( $this->lastErrno() ) {
 905                         throw new DBUnexpectedError( $this, 'Error in numRows(): ' . htmlspecialchars( $this->lastError() ) );
 906                 }
 907                 return $n;
 908         }
 909
 910         /**
 911          * Get the number of fields in a result object
 912          * See documentation for mysql_num_fields()
 913          */
 914         function numFields( $res ) { return mysql_num_fields( $res ); }
 915
 916         /**
 917          * Get a field name in a result object
 918          * See documentation for mysql_field_name():
 919          * http://www.php.net/mysql_field_name
 920          */
 921         function fieldName( $res, $n ) { return mysql_field_name( $res, $n ); }
 922
 923         /**
 924          * Get the inserted value of an auto-increment row
 925          *
 926          * The value inserted should be fetched from nextSequenceValue()
 927          *
 928          * Example:
 929          * $id = $dbw->nextSequenceValue('page_page_id_seq');
 930          * $dbw->insert('page',array('page_id' => $id));
 931          * $id = $dbw->insertId();
 932          */
 933         function insertId() { return mysql_insert_id( $this->mConn ); }
 934
 935         /**
 936          * Change the position of the cursor in a result object
 937          * See mysql_data_seek()
 938          */
 939         function dataSeek( $res, $row ) { return mysql_data_seek( $res, $row ); }
 940
 941         /**
 942          * Get the last error number
 943          * See mysql_errno()
 944          */
 945         function lastErrno() {
 946                 if ( $this->mConn ) {
 947                         return mysql_errno( $this->mConn );
 948                 } else {
 949                         return mysql_errno();
 950                 }
 951         }
 952
 953         /**
 954          * Get a description of the last error
 955          * See mysql_error() for more details
 956          */
 957         function lastError() {
 958                 if ( $this->mConn ) {
 959                         # Even if it's non-zero, it can still be invalid
 960                         wfSuppressWarnings();
 961                         $error = mysql_error( $this->mConn );
 962                         if ( !$error ) {
 963                                 $error = mysql_error();
 964                         }
 965                         wfRestoreWarnings();
 966                 } else {
 967                         $error = mysql_error();
 968                 }
 969                 if( $error ) {
 970                         $error .= ' (' . $this->mServer . ')';
 971                 }
 972                 return $error;
 973         }
 974         /**
 975          * Get the number of rows affected by the last write query
 976          * See mysql_affected_rows() for more details
 977          */
 978         function affectedRows() { return mysql_affected_rows( $this->mConn ); }
 979         /**#@-*/ // end of template : @param $result
 980
 981         /**
 982          * Simple UPDATE wrapper
 983          * Usually aborts on failure
 984          * If errors are explicitly ignored, returns success
 985          *
 986          * This function exists for historical reasons, Database::update() has a more standard
 987          * calling convention and feature set
 988          */
 989         function set( $table, $var, $value, $cond, $fname = 'Database::set' )
 990         {
 991                 $table = $this->tableName( $table );
 992                 $sql = "UPDATE $table SET $var = '" .
 993                   $this->strencode( $value ) . "' WHERE ($cond)";
 994                 return (bool)$this->query( $sql, $fname );
 995         }
 996
 997         /**
 998          * Simple SELECT wrapper, returns a single field, input must be encoded
 999          * Usually aborts on failure
1000          * If errors are explicitly ignored, returns FALSE on failure
1001          */
1002         function selectField( $table, $var, $cond='', $fname = 'Database::selectField', $options = array() ) {
1003                 if ( !is_array( $options ) ) {
1004                         $options = array( $options );
1005                 }
1006                 $options['LIMIT'] = 1;
1007
1008                 $res = $this->select( $table, $var, $cond, $fname, $options );
1009                 if ( $res === false || !$this->numRows( $res ) ) {
1010                         return false;
1011                 }
1012                 $row = $this->fetchRow( $res );
1013                 if ( $row !== false ) {
1014                         $this->freeResult( $res );
1015                         return $row[0];
1016                 } else {
1017                         return false;
1018                 }
1019         }
1020
1021         /**
1022          * Returns an optional USE INDEX clause to go after the table, and a
1023          * string to go at the end of the query
1024          *
1025          * @private
1026          *
1027          * @param array $options an associative array of options to be turned into
1028          *              an SQL query, valid keys are listed in the function.
1029          * @return array
1030          */
1031         function makeSelectOptions( $options ) {
1032                 $preLimitTail = $postLimitTail = '';
1033                 $startOpts = '';
1034
1035                 $noKeyOptions = array();
1036                 foreach ( $options as $key => $option ) {
1037                         if ( is_numeric( $key ) ) {
1038                                 $noKeyOptions[$option] = true;
1039                         }
1040                 }
1041
1042                 if ( isset( $options['GROUP BY'] ) ) $preLimitTail .= " GROUP BY {$options['GROUP BY']}";
1043                 if ( isset( $options['ORDER BY'] ) ) $preLimitTail .= " ORDER BY {$options['ORDER BY']}";
1044
1045                 //if (isset($options['LIMIT'])) {
1046                 //      $tailOpts .= $this->limitResult('', $options['LIMIT'],
1047                 //              isset($options['OFFSET']) ? $options['OFFSET']
1048                 //              : false);
1049                 //}
1050
1051                 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) $postLimitTail .= ' FOR UPDATE';
1052                 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) $postLimitTail .= ' LOCK IN SHARE MODE';
1053                 if ( isset( $noKeyOptions['DISTINCT'] ) && isset( $noKeyOptions['DISTINCTROW'] ) ) $startOpts .= 'DISTINCT';
1054
1055                 # Various MySQL extensions
1056                 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) $startOpts .= ' /*! STRAIGHT_JOIN */';
1057                 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) $startOpts .= ' HIGH_PRIORITY';
1058                 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) $startOpts .= ' SQL_BIG_RESULT';
1059                 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) $startOpts .= ' SQL_BUFFER_RESULT';
1060                 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) $startOpts .= ' SQL_SMALL_RESULT';
1061                 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) $startOpts .= ' SQL_CALC_FOUND_ROWS';
1062                 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) $startOpts .= ' SQL_CACHE';
1063                 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) $startOpts .= ' SQL_NO_CACHE';
1064
1065                 if ( isset( $options['USE INDEX'] ) && ! is_array( $options['USE INDEX'] ) ) {
1066                         $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1067                 } else {
1068                         $useIndex = '';
1069                 }
1070
1071                 return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail );
1072         }
1073
1074         /**
1075          * SELECT wrapper
1076          *
1077          * @param mixed  $table   Array or string, table name(s) (prefix auto-added)
1078          * @param mixed  $vars    Array or string, field name(s) to be retrieved
1079          * @param mixed  $conds   Array or string, condition(s) for WHERE
1080          * @param string $fname   Calling function name (use __METHOD__) for logs/profiling
1081          * @param array  $options Associative array of options (e.g. array('GROUP BY' => 'page_title')),
1082          *                        see Database::makeSelectOptions code for list of supported stuff
1083          * @return mixed Database result resource (feed to Database::fetchObject or whatever), or false on failure
1084          */
1085         function select( $table, $vars, $conds='', $fname = 'Database::select', $options = array() )
1086         {
1087                 if( is_array( $vars ) ) {
1088                         $vars = implode( ',', $vars );
1089                 }
1090                 if( !is_array( $options ) ) {
1091                         $options = array( $options );
1092                 }
1093                 if( is_array( $table ) ) {
1094                         if ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1095                                 $from = ' FROM ' . $this->tableNamesWithUseIndex( $table, $options['USE INDEX'] );
1096                         else
1097                                 $from = ' FROM ' . implode( ',', array_map( array( &$this, 'tableName' ), $table ) );
1098                 } elseif ($table!='') {
1099                         if ($table{0}==' ') {
1100                                 $from = ' FROM ' . $table;
1101                         } else {
1102                                 $from = ' FROM ' . $this->tableName( $table );
1103                         }
1104                 } else {
1105                         $from = '';
1106                 }
1107
1108                 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail ) = $this->makeSelectOptions( $options );
1109
1110                 if( !empty( $conds ) ) {
1111                         if ( is_array( $conds ) ) {
1112                                 $conds = $this->makeList( $conds, LIST_AND );
1113                         }
1114                         $sql = "SELECT $startOpts $vars $from $useIndex WHERE $conds $preLimitTail";
1115                 } else {
1116                         $sql = "SELECT $startOpts $vars $from $useIndex $preLimitTail";
1117                 }
1118
1119                 if (isset($options['LIMIT']))
1120                         $sql = $this->limitResult($sql, $options['LIMIT'],
1121                                 isset($options['OFFSET']) ? $options['OFFSET'] : false);
1122                 $sql = "$sql $postLimitTail";
1123
1124                 return $this->query( $sql, $fname );
1125         }
1126
1127         /**
1128          * Single row SELECT wrapper
1129          * Aborts or returns FALSE on error
1130          *
1131          * $vars: the selected variables
1132          * $conds: a condition map, terms are ANDed together.
1133          *   Items with numeric keys are taken to be literal conditions
1134          * Takes an array of selected variables, and a condition map, which is ANDed
1135          * e.g: selectRow( "page", array( "page_id" ), array( "page_namespace" =>
1136          * NS_MAIN, "page_title" => "Astronomy" ) )   would return an object where
1137          * $obj- >page_id is the ID of the Astronomy article
1138          *
1139          * @todo migrate documentation to phpdocumentor format
1140          */
1141         function selectRow( $table, $vars, $conds, $fname = 'Database::selectRow', $options = array() ) {
1142                 $options['LIMIT'] = 1;
1143                 $res = $this->select( $table, $vars, $conds, $fname, $options );
1144                 if ( $res === false )
1145                         return false;
1146                 if ( !$this->numRows($res) ) {
1147                         $this->freeResult($res);
1148                         return false;
1149                 }
1150                 $obj = $this->fetchObject( $res );
1151                 $this->freeResult( $res );
1152                 return $obj;
1153
1154         }
1155
1156         /**
1157          * Removes most variables from an SQL query and replaces them with X or N for numbers.
1158          * It's only slightly flawed. Don't use for anything important.
1159          *
1160          * @param string $sql A SQL Query
1161          * @static
1162          */
1163         static function generalizeSQL( $sql ) {
1164                 # This does the same as the regexp below would do, but in such a way
1165                 # as to avoid crashing php on some large strings.
1166                 # $sql = preg_replace ( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql);
1167
1168                 $sql = str_replace ( "\\\\", '', $sql);
1169                 $sql = str_replace ( "\\'", '', $sql);
1170                 $sql = str_replace ( "\\\"", '', $sql);
1171                 $sql = preg_replace ("/'.*'/s", "'X'", $sql);
1172                 $sql = preg_replace ('/".*"/s', "'X'", $sql);
1173
1174                 # All newlines, tabs, etc replaced by single space
1175                 $sql = preg_replace ( '/\s+/', ' ', $sql);
1176
1177                 # All numbers => N
1178                 $sql = preg_replace ('/-?[0-9]+/s', 'N', $sql);
1179
1180                 return $sql;
1181         }
1182
1183         /**
1184          * Determines whether a field exists in a table
1185          * Usually aborts on failure
1186          * If errors are explicitly ignored, returns NULL on failure
1187          */
1188         function fieldExists( $table, $field, $fname = 'Database::fieldExists' ) {
1189                 $table = $this->tableName( $table );
1190                 $res = $this->query( 'DESCRIBE '.$table, $fname );
1191                 if ( !$res ) {
1192                         return NULL;
1193                 }
1194
1195                 $found = false;
1196
1197                 while ( $row = $this->fetchObject( $res ) ) {
1198                         if ( $row->Field == $field ) {
1199                                 $found = true;
1200                                 break;
1201                         }
1202                 }
1203                 return $found;
1204         }
1205
1206         /**
1207          * Determines whether an index exists
1208          * Usually aborts on failure
1209          * If errors are explicitly ignored, returns NULL on failure
1210          */
1211         function indexExists( $table, $index, $fname = 'Database::indexExists' ) {
1212                 $info = $this->indexInfo( $table, $index, $fname );
1213                 if ( is_null( $info ) ) {
1214                         return NULL;
1215                 } else {
1216                         return $info !== false;
1217                 }
1218         }
1219
1220
1221         /**
1222          * Get information about an index into an object
1223          * Returns false if the index does not exist
1224          */
1225         function indexInfo( $table, $index, $fname = 'Database::indexInfo' ) {
1226                 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
1227                 # SHOW INDEX should work for 3.x and up:
1228                 # http://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
1229                 $table = $this->tableName( $table );
1230                 $sql = 'SHOW INDEX FROM '.$table;
1231                 $res = $this->query( $sql, $fname );
1232                 if ( !$res ) {
1233                         return NULL;
1234                 }
1235
1236                 $result = array();
1237                 while ( $row = $this->fetchObject( $res ) ) {
1238                         if ( $row->Key_name == $index ) {
1239                                 $result[] = $row;
1240                         }
1241                 }
1242                 $this->freeResult($res);
1243
1244                 return empty($result) ? false : $result;
1245         }
1246
1247         /**
1248          * Query whether a given table exists
1249          */
1250         function tableExists( $table ) {
1251                 $table = $this->tableName( $table );
1252                 $old = $this->ignoreErrors( true );
1253                 $res = $this->query( "SELECT 1 FROM $table LIMIT 1" );
1254                 $this->ignoreErrors( $old );
1255                 if( $res ) {
1256                         $this->freeResult( $res );
1257                         return true;
1258                 } else {
1259                         return false;
1260                 }
1261         }
1262
1263         /**
1264          * mysql_fetch_field() wrapper
1265          * Returns false if the field doesn't exist
1266          *
1267          * @param $table
1268          * @param $field
1269          */
1270         function fieldInfo( $table, $field ) {
1271                 $table = $this->tableName( $table );
1272                 $res = $this->query( "SELECT * FROM $table LIMIT 1" );
1273                 $n = mysql_num_fields( $res );
1274                 for( $i = 0; $i < $n; $i++ ) {
1275                         $meta = mysql_fetch_field( $res, $i );
1276                         if( $field == $meta->name ) {
1277                                 return new MySQLField($meta);
1278                         }
1279                 }
1280                 return false;
1281         }
1282
1283         /**
1284          * mysql_field_type() wrapper
1285          */
1286         function fieldType( $res, $index ) {
1287                 return mysql_field_type( $res, $index );
1288         }
1289
1290         /**
1291          * Determines if a given index is unique
1292          */
1293         function indexUnique( $table, $index ) {
1294                 $indexInfo = $this->indexInfo( $table, $index );
1295                 if ( !$indexInfo ) {
1296                         return NULL;
1297                 }
1298                 return !$indexInfo[0]->Non_unique;
1299         }
1300
1301         /**
1302          * INSERT wrapper, inserts an array into a table
1303          *
1304          * $a may be a single associative array, or an array of these with numeric keys, for
1305          * multi-row insert.
1306          *
1307          * Usually aborts on failure
1308          * If errors are explicitly ignored, returns success
1309          */
1310         function insert( $table, $a, $fname = 'Database::insert', $options = array() ) {
1311                 # No rows to insert, easy just return now
1312                 if ( !count( $a ) ) {
1313                         return true;
1314                 }
1315
1316                 $table = $this->tableName( $table );
1317                 if ( !is_array( $options ) ) {
1318                         $options = array( $options );
1319                 }
1320                 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
1321                         $multi = true;
1322                         $keys = array_keys( $a[0] );
1323                 } else {
1324                         $multi = false;
1325                         $keys = array_keys( $a );
1326                 }
1327
1328                 $sql = 'INSERT ' . implode( ' ', $options ) .
1329                         " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
1330
1331                 if ( $multi ) {
1332                         $first = true;
1333                         foreach ( $a as $row ) {
1334                                 if ( $first ) {
1335                                         $first = false;
1336                                 } else {
1337                                         $sql .= ',';
1338                                 }
1339                                 $sql .= '(' . $this->makeList( $row ) . ')';
1340                         }
1341                 } else {
1342                         $sql .= '(' . $this->makeList( $a ) . ')';
1343                 }
1344                 return (bool)$this->query( $sql, $fname );
1345         }
1346
1347         /**
1348          * Make UPDATE options for the Database::update function
1349          *
1350          * @private
1351          * @param array $options The options passed to Database::update
1352          * @return string
1353          */
1354         function makeUpdateOptions( $options ) {
1355                 if( !is_array( $options ) ) {
1356                         $options = array( $options );
1357                 }
1358                 $opts = array();
1359                 if ( in_array( 'LOW_PRIORITY', $options ) )
1360                         $opts[] = $this->lowPriorityOption();
1361                 if ( in_array( 'IGNORE', $options ) )
1362                         $opts[] = 'IGNORE';
1363                 return implode(' ', $opts);
1364         }
1365
1366         /**
1367          * UPDATE wrapper, takes a condition array and a SET array
1368          *
1369          * @param string $table  The table to UPDATE
1370          * @param array  $values An array of values to SET
1371          * @param array  $conds  An array of conditions (WHERE). Use '*' to update all rows.
1372          * @param string $fname  The Class::Function calling this function
1373          *                       (for the log)
1374          * @param array  $options An array of UPDATE options, can be one or
1375          *                        more of IGNORE, LOW_PRIORITY
1376          */
1377         function update( $table, $values, $conds, $fname = 'Database::update', $options = array() ) {
1378                 $table = $this->tableName( $table );
1379                 $opts = $this->makeUpdateOptions( $options );
1380                 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, LIST_SET );
1381                 if ( $conds != '*' ) {
1382                         $sql .= " WHERE " . $this->makeList( $conds, LIST_AND );
1383                 }
1384                 $this->query( $sql, $fname );
1385         }
1386
1387         /**
1388          * Makes an encoded list of strings from an array
1389          * $mode:
1390          *        LIST_COMMA         - comma separated, no field names
1391          *        LIST_AND           - ANDed WHERE clause (without the WHERE)
1392          *        LIST_OR            - ORed WHERE clause (without the WHERE)
1393          *        LIST_SET           - comma separated with field names, like a SET clause
1394          *        LIST_NAMES         - comma separated field names
1395          */
1396         function makeList( $a, $mode = LIST_COMMA ) {
1397                 if ( !is_array( $a ) ) {
1398                         throw new DBUnexpectedError( $this, 'Database::makeList called with incorrect parameters' );
1399                 }
1400
1401                 $first = true;
1402                 $list = '';
1403                 foreach ( $a as $field => $value ) {
1404                         if ( !$first ) {
1405                                 if ( $mode == LIST_AND ) {
1406                                         $list .= ' AND ';
1407                                 } elseif($mode == LIST_OR) {
1408                                         $list .= ' OR ';
1409                                 } else {
1410                                         $list .= ',';
1411                                 }
1412                         } else {
1413                                 $first = false;
1414                         }
1415                         if ( ($mode == LIST_AND || $mode == LIST_OR) && is_numeric( $field ) ) {
1416                                 $list .= "($value)";
1417                         } elseif ( ($mode == LIST_SET) && is_numeric( $field ) ) {
1418                                 $list .= "$value";
1419                         } elseif ( ($mode == LIST_AND || $mode == LIST_OR) && is_array ($value) ) {
1420                                 $list .= $field." IN (".$this->makeList($value).") ";
1421                         } else {
1422                                 if ( $mode == LIST_AND || $mode == LIST_OR || $mode == LIST_SET ) {
1423                                         $list .= "$field = ";
1424                                 }
1425                                 $list .= $mode == LIST_NAMES ? $value : $this->addQuotes( $value );
1426                         }
1427                 }
1428                 return $list;
1429         }
1430
1431         /**
1432          * Change the current database
1433          */
1434         function selectDB( $db ) {
1435                 $this->mDBname = $db;
1436                 return mysql_select_db( $db, $this->mConn );
1437         }
1438
1439         /**
1440          * Format a table name ready for use in constructing an SQL query
1441          *
1442          * This does two important things: it quotes table names which as necessary,
1443          * and it adds a table prefix if there is one.
1444          *
1445          * All functions of this object which require a table name call this function
1446          * themselves. Pass the canonical name to such functions. This is only needed
1447          * when calling query() directly.
1448          *
1449          * @param string $name database table name
1450          */
1451         function tableName( $name ) {
1452                 global $wgSharedDB;
1453                 # Skip quoted literals
1454                 if ( $name{0} != '`' ) {
1455                         if ( $this->mTablePrefix !== '' &&  strpos( '.', $name ) === false ) {
1456                                 $name = "{$this->mTablePrefix}$name";
1457                         }
1458                         if ( isset( $wgSharedDB ) && "{$this->mTablePrefix}user" == $name ) {
1459                                 $name = "`$wgSharedDB`.`$name`";
1460                         } else {
1461                                 # Standard quoting
1462                                 $name = "`$name`";
1463                         }
1464                 }
1465                 return $name;
1466         }
1467
1468         /**
1469          * Fetch a number of table names into an array
1470          * This is handy when you need to construct SQL for joins
1471          *
1472          * Example:
1473          * extract($dbr->tableNames('user','watchlist'));
1474          * $sql = "SELECT wl_namespace,wl_title FROM $watchlist,$user
1475          *         WHERE wl_user=user_id AND wl_user=$nameWithQuotes";
1476          */
1477         public function tableNames() {
1478                 $inArray = func_get_args();
1479                 $retVal = array();
1480                 foreach ( $inArray as $name ) {
1481                         $retVal[$name] = $this->tableName( $name );
1482                 }
1483                 return $retVal;
1484         }
1485
1486         /**
1487          * @desc: Fetch a number of table names into an zero-indexed numerical array
1488          * This is handy when you need to construct SQL for joins
1489          *
1490          * Example:
1491          * list( $user, $watchlist ) = $dbr->tableNames('user','watchlist');
1492          * $sql = "SELECT wl_namespace,wl_title FROM $watchlist,$user
1493          *         WHERE wl_user=user_id AND wl_user=$nameWithQuotes";
1494          */
1495         public function tableNamesN() {
1496                 $inArray = func_get_args();
1497                 $retVal = array();
1498                 foreach ( $inArray as $name ) {
1499                         $retVal[] = $this->tableName( $name );
1500                 }
1501                 return $retVal;
1502         }
1503
1504         /**
1505          * @private
1506          */
1507         function tableNamesWithUseIndex( $tables, $use_index ) {
1508                 $ret = array();
1509
1510                 foreach ( $tables as $table )
1511                         if ( @$use_index[$table] !== null )
1512                                 $ret[] = $this->tableName( $table ) . ' ' . $this->useIndexClause( implode( ',', (array)$use_index[$table] ) );
1513                         else
1514                                 $ret[] = $this->tableName( $table );
1515
1516                 return implode( ',', $ret );
1517         }
1518
1519         /**
1520          * Wrapper for addslashes()
1521          * @param string $s String to be slashed.
1522          * @return string slashed string.
1523          */
1524         function strencode( $s ) {
1525                 return mysql_real_escape_string( $s, $this->mConn );
1526         }
1527
1528         /**
1529          * If it's a string, adds quotes and backslashes
1530          * Otherwise returns as-is
1531          */
1532         function addQuotes( $s ) {
1533                 if ( is_null( $s ) ) {
1534                         return 'NULL';
1535                 } else {
1536                         # This will also quote numeric values. This should be harmless,
1537                         # and protects against weird problems that occur when they really
1538                         # _are_ strings such as article titles and string->number->string
1539                         # conversion is not 1:1.
1540                         return "'" . $this->strencode( $s ) . "'";
1541                 }
1542         }
1543
1544         /**
1545          * Escape string for safe LIKE usage
1546          */
1547         function escapeLike( $s ) {
1548                 $s=$this->strencode( $s );
1549                 $s=str_replace(array('%','_'),array('\%','\_'),$s);
1550                 return $s;
1551         }
1552
1553         /**
1554          * Returns an appropriately quoted sequence value for inserting a new row.
1555          * MySQL has autoincrement fields, so this is just NULL. But the PostgreSQL
1556          * subclass will return an integer, and save the value for insertId()
1557          */
1558         function nextSequenceValue( $seqName ) {
1559                 return NULL;
1560         }
1561
1562         /**
1563          * USE INDEX clause
1564          * PostgreSQL doesn't have them and returns ""
1565          */
1566         function useIndexClause( $index ) {
1567                 return "FORCE INDEX ($index)";
1568         }
1569
1570         /**
1571          * REPLACE query wrapper
1572          * PostgreSQL simulates this with a DELETE followed by INSERT
1573          * $row is the row to insert, an associative array
1574          * $uniqueIndexes is an array of indexes. Each element may be either a
1575          * field name or an array of field names
1576          *
1577          * It may be more efficient to leave off unique indexes which are unlikely to collide.
1578          * However if you do this, you run the risk of encountering errors which wouldn't have
1579          * occurred in MySQL
1580          *
1581          * @todo migrate comment to phodocumentor format
1582          */
1583         function replace( $table, $uniqueIndexes, $rows, $fname = 'Database::replace' ) {
1584                 $table = $this->tableName( $table );
1585
1586                 # Single row case
1587                 if ( !is_array( reset( $rows ) ) ) {
1588                         $rows = array( $rows );
1589                 }
1590
1591                 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) .') VALUES ';
1592                 $first = true;
1593                 foreach ( $rows as $row ) {
1594                         if ( $first ) {
1595                                 $first = false;
1596                         } else {
1597                                 $sql .= ',';
1598                         }
1599                         $sql .= '(' . $this->makeList( $row ) . ')';
1600                 }
1601                 return $this->query( $sql, $fname );
1602         }
1603
1604         /**
1605          * DELETE where the condition is a join
1606          * MySQL does this with a multi-table DELETE syntax, PostgreSQL does it with sub-selects
1607          *
1608          * For safety, an empty $conds will not delete everything. If you want to delete all rows where the
1609          * join condition matches, set $conds='*'
1610          *
1611          * DO NOT put the join condition in $conds
1612          *
1613          * @param string $delTable The table to delete from.
1614          * @param string $joinTable The other table.
1615          * @param string $delVar The variable to join on, in the first table.
1616          * @param string $joinVar The variable to join on, in the second table.
1617          * @param array $conds Condition array of field names mapped to variables, ANDed together in the WHERE clause
1618          */
1619         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = 'Database::deleteJoin' ) {
1620                 if ( !$conds ) {
1621                         throw new DBUnexpectedError( $this, 'Database::deleteJoin() called with empty $conds' );
1622                 }
1623
1624                 $delTable = $this->tableName( $delTable );
1625                 $joinTable = $this->tableName( $joinTable );
1626                 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
1627                 if ( $conds != '*' ) {
1628                         $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
1629                 }
1630
1631                 return $this->query( $sql, $fname );
1632         }
1633
1634         /**
1635          * Returns the size of a text field, or -1 for "unlimited"
1636          */
1637         function textFieldSize( $table, $field ) {
1638                 $table = $this->tableName( $table );
1639                 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
1640                 $res = $this->query( $sql, 'Database::textFieldSize' );
1641                 $row = $this->fetchObject( $res );
1642                 $this->freeResult( $res );
1643
1644                 $m = array();
1645                 if ( preg_match( '/\((.*)\)/', $row->Type, $m ) ) {
1646                         $size = $m[1];
1647                 } else {
1648                         $size = -1;
1649                 }
1650                 return $size;
1651         }
1652
1653         /**
1654          * @return string Returns the text of the low priority option if it is supported, or a blank string otherwise
1655          */
1656         function lowPriorityOption() {
1657                 return 'LOW_PRIORITY';
1658         }
1659
1660         /**
1661          * DELETE query wrapper
1662          *
1663          * Use $conds == "*" to delete all rows
1664          */
1665         function delete( $table, $conds, $fname = 'Database::delete' ) {
1666                 if ( !$conds ) {
1667                         throw new DBUnexpectedError( $this, 'Database::delete() called with no conditions' );
1668                 }
1669                 $table = $this->tableName( $table );
1670                 $sql = "DELETE FROM $table";
1671                 if ( $conds != '*' ) {
1672                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
1673                 }
1674                 return $this->query( $sql, $fname );
1675         }
1676
1677         /**
1678          * INSERT SELECT wrapper
1679          * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
1680          * Source items may be literals rather than field names, but strings should be quoted with Database::addQuotes()
1681          * $conds may be "*" to copy the whole table
1682          * srcTable may be an array of tables.
1683          */
1684         function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = 'Database::insertSelect',
1685                 $insertOptions = array(), $selectOptions = array() )
1686         {
1687                 $destTable = $this->tableName( $destTable );
1688                 if ( is_array( $insertOptions ) ) {
1689                         $insertOptions = implode( ' ', $insertOptions );
1690                 }
1691                 if( !is_array( $selectOptions ) ) {
1692                         $selectOptions = array( $selectOptions );
1693                 }
1694                 list( $startOpts, $useIndex, $tailOpts ) = $this->makeSelectOptions( $selectOptions );
1695                 if( is_array( $srcTable ) ) {
1696                         $srcTable =  implode( ',', array_map( array( &$this, 'tableName' ), $srcTable ) );
1697                 } else {
1698                         $srcTable = $this->tableName( $srcTable );
1699                 }
1700                 $sql = "INSERT $insertOptions INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' .
1701                         " SELECT $startOpts " . implode( ',', $varMap ) .
1702                         " FROM $srcTable $useIndex ";
1703                 if ( $conds != '*' ) {
1704                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
1705                 }
1706                 $sql .= " $tailOpts";
1707                 return $this->query( $sql, $fname );
1708         }
1709
1710         /**
1711          * Construct a LIMIT query with optional offset
1712          * This is used for query pages
1713          * $sql string SQL query we will append the limit too
1714          * $limit integer the SQL limit
1715          * $offset integer the SQL offset (default false)
1716          */
1717         function limitResult($sql, $limit, $offset=false) {
1718                 if( !is_numeric($limit) ) {
1719                         throw new DBUnexpectedError( $this, "Invalid non-numeric limit passed to limitResult()\n" );
1720                 }
1721                 return " $sql LIMIT "
1722                                 . ( (is_numeric($offset) && $offset != 0) ? "{$offset}," : "" )
1723                                 . "{$limit} ";
1724         }
1725         function limitResultForUpdate($sql, $num) {
1726                 return $this->limitResult($sql, $num, 0);
1727         }
1728
1729         /**
1730          * Returns an SQL expression for a simple conditional.
1731          * Uses IF on MySQL.
1732          *
1733          * @param string $cond SQL expression which will result in a boolean value
1734          * @param string $trueVal SQL expression to return if true
1735          * @param string $falseVal SQL expression to return if false
1736          * @return string SQL fragment
1737          */
1738         function conditional( $cond, $trueVal, $falseVal ) {
1739                 return " IF($cond, $trueVal, $falseVal) ";
1740         }
1741
1742         /**
1743          * Determines if the last failure was due to a deadlock
1744          */
1745         function wasDeadlock() {
1746                 return $this->lastErrno() == 1213;
1747         }
1748
1749         /**
1750          * Perform a deadlock-prone transaction.
1751          *
1752          * This function invokes a callback function to perform a set of write
1753          * queries. If a deadlock occurs during the processing, the transaction
1754          * will be rolled back and the callback function will be called again.
1755          *
1756          * Usage:
1757          *   $dbw->deadlockLoop( callback, ... );
1758          *
1759          * Extra arguments are passed through to the specified callback function.
1760          *
1761          * Returns whatever the callback function returned on its successful,
1762          * iteration, or false on error, for example if the retry limit was
1763          * reached.
1764          */
1765         function deadlockLoop() {
1766                 $myFname = 'Database::deadlockLoop';
1767
1768                 $this->begin();
1769                 $args = func_get_args();
1770                 $function = array_shift( $args );
1771                 $oldIgnore = $this->ignoreErrors( true );
1772                 $tries = DEADLOCK_TRIES;
1773                 if ( is_array( $function ) ) {
1774                         $fname = $function[0];
1775                 } else {
1776                         $fname = $function;
1777                 }
1778                 do {
1779                         $retVal = call_user_func_array( $function, $args );
1780                         $error = $this->lastError();
1781                         $errno = $this->lastErrno();
1782                         $sql = $this->lastQuery();
1783
1784                         if ( $errno ) {
1785                                 if ( $this->wasDeadlock() ) {
1786                                         # Retry
1787                                         usleep( mt_rand( DEADLOCK_DELAY_MIN, DEADLOCK_DELAY_MAX ) );
1788                                 } else {
1789                                         $this->reportQueryError( $error, $errno, $sql, $fname );
1790                                 }
1791                         }
1792                 } while( $this->wasDeadlock() && --$tries > 0 );
1793                 $this->ignoreErrors( $oldIgnore );
1794                 if ( $tries <= 0 ) {
1795                         $this->query( 'ROLLBACK', $myFname );
1796                         $this->reportQueryError( $error, $errno, $sql, $fname );
1797                         return false;
1798                 } else {
1799                         $this->query( 'COMMIT', $myFname );
1800                         return $retVal;
1801                 }
1802         }
1803
1804         /**
1805          * Do a SELECT MASTER_POS_WAIT()
1806          *
1807          * @param string $file the binlog file
1808          * @param string $pos the binlog position
1809          * @param integer $timeout the maximum number of seconds to wait for synchronisation
1810          */
1811         function masterPosWait( $file, $pos, $timeout ) {
1812                 $fname = 'Database::masterPosWait';
1813                 wfProfileIn( $fname );
1814
1815
1816                 # Commit any open transactions
1817                 $this->immediateCommit();
1818
1819                 # Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
1820                 $encFile = $this->strencode( $file );
1821                 $sql = "SELECT MASTER_POS_WAIT('$encFile', $pos, $timeout)";
1822                 $res = $this->doQuery( $sql );
1823                 if ( $res && $row = $this->fetchRow( $res ) ) {
1824                         $this->freeResult( $res );
1825                         wfProfileOut( $fname );
1826                         return $row[0];
1827                 } else {
1828                         wfProfileOut( $fname );
1829                         return false;
1830                 }
1831         }
1832
1833         /**
1834          * Get the position of the master from SHOW SLAVE STATUS
1835          */
1836         function getSlavePos() {
1837                 $res = $this->query( 'SHOW SLAVE STATUS', 'Database::getSlavePos' );
1838                 $row = $this->fetchObject( $res );
1839                 if ( $row ) {
1840                         return array( $row->Master_Log_File, $row->Read_Master_Log_Pos );
1841                 } else {
1842                         return array( false, false );
1843                 }
1844         }
1845
1846         /**
1847          * Get the position of the master from SHOW MASTER STATUS
1848          */
1849         function getMasterPos() {
1850                 $res = $this->query( 'SHOW MASTER STATUS', 'Database::getMasterPos' );
1851                 $row = $this->fetchObject( $res );
1852                 if ( $row ) {
1853                         return array( $row->File, $row->Position );
1854                 } else {
1855                         return array( false, false );
1856                 }
1857         }
1858
1859         /**
1860          * Begin a transaction, committing any previously open transaction
1861          */
1862         function begin( $fname = 'Database::begin' ) {
1863                 $this->query( 'BEGIN', $fname );
1864                 $this->mTrxLevel = 1;
1865         }
1866
1867         /**
1868          * End a transaction
1869          */
1870         function commit( $fname = 'Database::commit' ) {
1871                 $this->query( 'COMMIT', $fname );
1872                 $this->mTrxLevel = 0;
1873         }
1874
1875         /**
1876          * Rollback a transaction
1877          */
1878         function rollback( $fname = 'Database::rollback' ) {
1879                 $this->query( 'ROLLBACK', $fname );
1880                 $this->mTrxLevel = 0;
1881         }
1882
1883         /**
1884          * Begin a transaction, committing any previously open transaction
1885          * @deprecated use begin()
1886          */
1887         function immediateBegin( $fname = 'Database::immediateBegin' ) {
1888                 $this->begin();
1889         }
1890
1891         /**
1892          * Commit transaction, if one is open
1893          * @deprecated use commit()
1894          */
1895         function immediateCommit( $fname = 'Database::immediateCommit' ) {
1896                 $this->commit();
1897         }
1898
1899         /**
1900          * Return MW-style timestamp used for MySQL schema
1901          */
1902         function timestamp( $ts=0 ) {
1903                 return wfTimestamp(TS_MW,$ts);
1904         }
1905
1906         /**
1907          * Local database timestamp format or null
1908          */
1909         function timestampOrNull( $ts = null ) {
1910                 if( is_null( $ts ) ) {
1911                         return null;
1912                 } else {
1913                         return $this->timestamp( $ts );
1914                 }
1915         }
1916
1917         /**
1918          * @todo document
1919          */
1920         function resultObject( $result ) {
1921                 if( empty( $result ) ) {
1922                         return NULL;
1923                 } else {
1924                         return new ResultWrapper( $this, $result );
1925                 }
1926         }
1927
1928         /**
1929          * Return aggregated value alias
1930          */
1931         function aggregateValue ($valuedata,$valuename='value') {
1932                 return $valuename;
1933         }
1934
1935         /**
1936          * @return string wikitext of a link to the server software's web site
1937          */
1938         function getSoftwareLink() {
1939                 return "[http://www.mysql.com/ MySQL]";
1940         }
1941
1942         /**
1943          * @return string Version information from the database
1944          */
1945         function getServerVersion() {
1946                 return mysql_get_server_info( $this->mConn );
1947         }
1948
1949         /**
1950          * Ping the server and try to reconnect if it there is no connection
1951          */
1952         function ping() {
1953                 if( function_exists( 'mysql_ping' ) ) {
1954                         return mysql_ping( $this->mConn );
1955                 } else {
1956                         wfDebug( "Tried to call mysql_ping but this is ancient PHP version. Faking it!\n" );
1957                         return true;
1958                 }
1959         }
1960
1961         /**
1962          * Get slave lag.
1963          * At the moment, this will only work if the DB user has the PROCESS privilege
1964          */
1965         function getLag() {
1966                 $res = $this->query( 'SHOW PROCESSLIST' );
1967                 # Find slave SQL thread. Assumed to be the second one running, which is a bit
1968                 # dubious, but unfortunately there's no easy rigorous way
1969                 while ( $row = $this->fetchObject( $res ) ) {
1970                         /* This should work for most situations - when default db
1971                          * for thread is not specified, it had no events executed,
1972                          * and therefore it doesn't know yet how lagged it is.
1973                          *
1974                          * Relay log I/O thread does not select databases.
1975                          */
1976                         if ( $row->User == 'system user' &&
1977                                 $row->State != 'Waiting for master to send event' &&
1978                                 $row->State != 'Connecting to master' &&
1979                                 $row->State != 'Queueing master event to the relay log' &&
1980                                 $row->State != 'Waiting for master update' &&
1981                                 $row->State != 'Requesting binlog dump'
1982                                 ) {
1983                                 # This is it, return the time (except -ve)
1984                                 if ( $row->Time > 0x7fffffff ) {
1985                                         return false;
1986                                 } else {
1987                                         return $row->Time;
1988                                 }
1989                         }
1990                 }
1991                 return false;
1992         }
1993
1994         /**
1995          * Get status information from SHOW STATUS in an associative array
1996          */
1997         function getStatus($which="%") {
1998                 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
1999                 $status = array();
2000                 while ( $row = $this->fetchObject( $res ) ) {
2001                         $status[$row->Variable_name] = $row->Value;
2002                 }
2003                 return $status;
2004         }
2005
2006         /**
2007          * Return the maximum number of items allowed in a list, or 0 for unlimited.
2008          */
2009         function maxListLen() {
2010                 return 0;
2011         }
2012
2013         function encodeBlob($b) {
2014                 return $b;
2015         }
2016
2017         function decodeBlob($b) {
2018                 return $b;
2019         }
2020
2021         /**
2022          * Override database's default connection timeout.
2023          * May be useful for very long batch queries such as
2024          * full-wiki dumps, where a single query reads out
2025          * over hours or days.
2026          * @param int $timeout in seconds
2027          */
2028         public function setTimeout( $timeout ) {
2029                 $this->query( "SET net_read_timeout=$timeout" );
2030                 $this->query( "SET net_write_timeout=$timeout" );
2031         }
2032
2033         /**
2034          * Read and execute SQL commands from a file.
2035          * Returns true on success, error string on failure
2036          */
2037         function sourceFile( $filename ) {
2038                 $fp = fopen( $filename, 'r' );
2039                 if ( false === $fp ) {
2040                         return "Could not open \"{$filename}\".\n";
2041                 }
2042
2043                 $cmd = "";
2044                 $done = false;
2045                 $dollarquote = false;
2046
2047                 while ( ! feof( $fp ) ) {
2048                         $line = trim( fgets( $fp, 1024 ) );
2049                         $sl = strlen( $line ) - 1;
2050
2051                         if ( $sl < 0 ) { continue; }
2052                         if ( '-' == $line{0} && '-' == $line{1} ) { continue; }
2053
2054                         ## Allow dollar quoting for function declarations
2055                         if (substr($line,0,4) == '$mw$') {
2056                                 if ($dollarquote) {
2057                                         $dollarquote = false;
2058                                         $done = true;
2059                                 }
2060                                 else {
2061                                         $dollarquote = true;
2062                                 }
2063                         }
2064                         else if (!$dollarquote) {
2065                                 if ( ';' == $line{$sl} && ($sl < 2 || ';' != $line{$sl - 1})) {
2066                                         $done = true;
2067                                         $line = substr( $line, 0, $sl );
2068                                 }
2069                         }
2070
2071                         if ( '' != $cmd ) { $cmd .= ' '; }
2072                         $cmd .= "$line\n";
2073
2074                         if ( $done ) {
2075                                 $cmd = str_replace(';;', ";", $cmd);
2076                                 $cmd = $this->replaceVars( $cmd );
2077                                 $res = $this->query( $cmd, 'dbsource', true );
2078
2079                                 if ( false === $res ) {
2080                                         $err = $this->lastError();
2081                                         return "Query \"{$cmd}\" failed with error code \"$err\".\n";
2082                                 }
2083
2084                                 $cmd = '';
2085                                 $done = false;
2086                         }
2087                 }
2088                 fclose( $fp );
2089                 return true;
2090         }
2091
2092         /**
2093          * Replace variables in sourced SQL
2094          */
2095         protected function replaceVars( $ins ) {
2096                 $varnames = array(
2097                         'wgDBserver', 'wgDBname', 'wgDBintlname', 'wgDBuser',
2098                         'wgDBpassword', 'wgDBsqluser', 'wgDBsqlpassword',
2099                         'wgDBadminuser', 'wgDBadminpassword',
2100                 );
2101
2102                 // Ordinary variables
2103                 foreach ( $varnames as $var ) {
2104                         if( isset( $GLOBALS[$var] ) ) {
2105                                 $val = addslashes( $GLOBALS[$var] ); // FIXME: safety check?
2106                                 $ins = str_replace( '{$' . $var . '}', $val, $ins );
2107                                 $ins = str_replace( '/*$' . $var . '*/`', '`' . $val, $ins );
2108                                 $ins = str_replace( '/*$' . $var . '*/', $val, $ins );
2109                         }
2110                 }
2111
2112                 // Table prefixes
2113                 $ins = preg_replace_callback( '/\/\*(?:\$wgDBprefix|_)\*\/([a-z_]*)/',
2114                         array( &$this, 'tableNameCallback' ), $ins );
2115                 return $ins;
2116         }
2117
2118         /**
2119          * Table name callback
2120          * @private
2121          */
2122         protected function tableNameCallback( $matches ) {
2123                 return $this->tableName( $matches[1] );
2124         }
2125
2126 }
2127
2128 /**
2129  * Database abstraction object for mySQL
2130  * Inherit all methods and properties of Database::Database()
2131  *
2132  * @see Database
2133  */
2134 class DatabaseMysql extends Database {
2135         # Inherit all
2136 }
2137
2138
2139 /**
2140  * Result wrapper for grabbing data queried by someone else
2141  *
2142  */
2143 class ResultWrapper {
2144         var $db, $result;
2145
2146         /**
2147          * @todo document
2148          */
2149         function ResultWrapper( &$database, $result ) {
2150                 $this->db =& $database;
2151                 $this->result =& $result;
2152         }
2153
2154         /**
2155          * @todo document
2156          */
2157         function numRows() {
2158                 return $this->db->numRows( $this->result );
2159         }
2160
2161         /**
2162          * @todo document
2163          */
2164         function fetchObject() {
2165                 return $this->db->fetchObject( $this->result );
2166         }
2167
2168         /**
2169          * @todo document
2170          */
2171         function fetchRow() {
2172                 return $this->db->fetchRow( $this->result );
2173         }
2174
2175         /**
2176          * @todo document
2177          */
2178         function free() {
2179                 $this->db->freeResult( $this->result );
2180                 unset( $this->result );
2181                 unset( $this->db );
2182         }
2183
2184         function seek( $row ) {
2185                 $this->db->dataSeek( $this->result, $row );
2186         }
2187
2188         function rewind() {
2189                 if ($this->numRows()) {
2190                         $this->db->dataSeek($this->result, 0);
2191                 }
2192         }
2193
2194 }
2195
2196 ?>