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