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 /**
  19  * Utility class.
  20  */
  21 class DBObject {
  22         public $mData;
  23
  24         function DBObject($data) {
  25                 $this->mData = $data;
  26         }
  27
  28         function isLOB() {
  29                 return false;
  30         }
  31
  32         function data() {
  33                 return $this->mData;
  34         }
  35 };
  36
  37 /**
  38  * Utility class.
  39  */
  40 class MySQLField {
  41         private $name, $tablename, $default, $max_length, $nullable,
  42                 $is_pk, $is_unique, $is_key, $type;
  43         function __construct ($info) {
  44                 $this->name = $info->name;
  45                 $this->tablename = $info->table;
  46                 $this->default = $info->def;
  47                 $this->max_length = $info->max_length;
  48                 $this->nullable = !$info->not_null;
  49                 $this->is_pk = $info->primary_key;
  50                 $this->is_unique = $info->unique_key;
  51                 $this->is_multiple = $info->multiple_key;
  52                 $this->is_key = ($this->is_pk || $this->is_unique || $this->is_multiple);
  53                 $this->type = $info->type;
  54         }
  55
  56         function name() {
  57                 return $this->name;
  58         }
  59
  60         function tableName() {
  61                 return $this->tableName;
  62         }
  63
  64         function defaultValue() {
  65                 return $this->default;
  66         }
  67
  68         function maxLength() {
  69                 return $this->max_length;
  70         }
  71
  72         function nullable() {
  73                 return $this->nullable;
  74         }
  75
  76         function isKey() {
  77                 return $this->is_key;
  78         }
  79
  80         function isMultipleKey() {
  81                 return $this->is_multiple;
  82         }
  83
  84         function type() {
  85                 return $this->type;
  86         }
  87 }
  88
  89 /******************************************************************************
  90  * Error classes
  91  *****************************************************************************/
  92
  93 /**
  94  * Database error base class
  95  */
  96 class DBError extends MWException {
  97         public $db;
  98
  99         /**
 100          * Construct a database error
 101          * @param Database $db The database object which threw the error
 102          * @param string $error A simple error message to be used for debugging
 103          */
 104         function __construct( Database &$db, $error ) {
 105                 $this->db =& $db;
 106                 parent::__construct( $error );
 107         }
 108 }
 109
 110 class DBConnectionError extends DBError {
 111         public $error;
 112
 113         function __construct( Database &$db, $error = 'unknown error' ) {
 114                 $msg = 'DB connection error';
 115                 if ( trim( $error ) != '' ) {
 116                         $msg .= ": $error";
 117                 }
 118                 $this->error = $error;
 119                 parent::__construct( $db, $msg );
 120         }
 121
 122         function useOutputPage() {
 123                 // Not likely to work
 124                 return false;
 125         }
 126
 127         function useMessageCache() {
 128                 // Not likely to work
 129                 return false;
 130         }
 131
 132         function getText() {
 133                 return $this->getMessage() . "\n";
 134         }
 135
 136         function getLogMessage() {
 137                 # Don't send to the exception log
 138                 return false;
 139         }
 140
 141         function getPageTitle() {
 142                 global $wgSitename;
 143                 return "$wgSitename has a problem";
 144         }
 145
 146         function getHTML() {
 147                 global $wgTitle, $wgUseFileCache, $title, $wgInputEncoding;
 148                 global $wgSitename, $wgServer, $wgMessageCache;
 149
 150                 # I give up, Brion is right. Getting the message cache to work when there is no DB is tricky.
 151                 # Hard coding strings instead.
 152
 153                 $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>";
 154                 $mainpage = 'Main Page';
 155                 $searchdisabled = <<<EOT
 156 <p style="margin: 1.5em 2em 1em">$wgSitename search is disabled for performance reasons. You can search via Google in the meantime.
 157 <span style="font-size: 89%; display: block; margin-left: .2em">Note that their indexes of $wgSitename content may be out of date.</span></p>',
 158 EOT;
 159
 160                 $googlesearch = "
 161 <!-- SiteSearch Google -->
 162 <FORM method=GET action=\"http://www.google.com/search\">
 163 <TABLE bgcolor=\"#FFFFFF\"><tr><td>
 164 <A HREF=\"http://www.google.com/\">
 165 <IMG SRC=\"http://www.google.com/logos/Logo_40wht.gif\"
 166 border=\"0\" ALT=\"Google\"></A>
 167 </td>
 168 <td>
 169 <INPUT TYPE=text name=q size=31 maxlength=255 value=\"$1\">
 170 <INPUT type=submit name=btnG VALUE=\"Google Search\">
 171 <font size=-1>
 172 <input type=hidden name=domains value=\"$wgServer\"><br /><input type=radio name=sitesearch value=\"\"> WWW <input type=radio name=sitesearch value=\"$wgServer\" checked> $wgServer <br />
 173 <input type='hidden' name='ie' value='$2'>
 174 <input type='hidden' name='oe' value='$2'>
 175 </font>
 176 </td></tr></TABLE>
 177 </FORM>
 178 <!-- SiteSearch Google -->";
 179                 $cachederror = "The following is a cached copy of the requested page, and may not be up to date. ";
 180
 181                 # No database access
 182                 if ( is_object( $wgMessageCache ) ) {
 183                         $wgMessageCache->disable();
 184                 }
 185
 186                 if ( trim( $this->error ) == '' ) {
 187                         $this->error = $this->db->getProperty('mServer');
 188                 }
 189
 190                 $text = str_replace( '$1', $this->error, $noconnect );
 191                 $text .= wfGetSiteNotice();
 192
 193                 if($wgUseFileCache) {
 194                         if($wgTitle) {
 195                                 $t =& $wgTitle;
 196                         } else {
 197                                 if($title) {
 198                                         $t = Title::newFromURL( $title );
 199                                 } elseif (@/**/$_REQUEST['search']) {
 200                                         $search = $_REQUEST['search'];
 201                                         return $searchdisabled .
 202                                           str_replace( array( '$1', '$2' ), array( htmlspecialchars( $search ),
 203                                           $wgInputEncoding ), $googlesearch );
 204                                 } else {
 205                                         $t = Title::newFromText( $mainpage );
 206                                 }
 207                         }
 208
 209                         $cache = new HTMLFileCache( $t );
 210                         if( $cache->isFileCached() ) {
 211                                 // FIXME: $msg is not defined on the next line.
 212                                 $msg = '<p style="color: red"><b>'.$msg."<br />\n" .
 213                                         $cachederror . "</b></p>\n";
 214
 215                                 $tag = '<div id="article">';
 216                                 $text = str_replace(
 217                                         $tag,
 218                                         $tag . $msg,
 219                                         $cache->fetchPageText() );
 220                         }
 221                 }
 222
 223                 return $text;
 224         }
 225 }
 226
 227 class DBQueryError extends DBError {
 228         public $error, $errno, $sql, $fname;
 229
 230         function __construct( Database &$db, $error, $errno, $sql, $fname ) {
 231                 $message = "A database error has occurred\n" .
 232                   "Query: $sql\n" .
 233                   "Function: $fname\n" .
 234                   "Error: $errno $error\n";
 235
 236                 parent::__construct( $db, $message );
 237                 $this->error = $error;
 238                 $this->errno = $errno;
 239                 $this->sql = $sql;
 240                 $this->fname = $fname;
 241         }
 242
 243         function getText() {
 244                 if ( $this->useMessageCache() ) {
 245                         return wfMsg( 'dberrortextcl', htmlspecialchars( $this->getSQL() ),
 246                           htmlspecialchars( $this->fname ), $this->errno, htmlspecialchars( $this->error ) ) . "\n";
 247                 } else {
 248                         return $this->getMessage();
 249                 }
 250         }
 251
 252         function getSQL() {
 253                 global $wgShowSQLErrors;
 254                 if( !$wgShowSQLErrors ) {
 255                         return $this->msg( 'sqlhidden', 'SQL hidden' );
 256                 } else {
 257                         return $this->sql;
 258                 }
 259         }
 260
 261         function getLogMessage() {
 262                 # Don't send to the exception log
 263                 return false;
 264         }
 265
 266         function getPageTitle() {
 267                 return $this->msg( 'databaseerror', 'Database error' );
 268         }
 269
 270         function getHTML() {
 271                 if ( $this->useMessageCache() ) {
 272                         return wfMsgNoDB( 'dberrortext', htmlspecialchars( $this->getSQL() ),
 273                           htmlspecialchars( $this->fname ), $this->errno, htmlspecialchars( $this->error ) );
 274                 } else {
 275                         return nl2br( htmlspecialchars( $this->getMessage() ) );
 276                 }
 277         }
 278 }
 279
 280 class DBUnexpectedError extends DBError {}
 281
 282 /******************************************************************************/
 283
 284 /**
 285  * Database abstraction object
 286  */
 287 class Database {
 288
 289 #------------------------------------------------------------------------------
 290 # Variables
 291 #------------------------------------------------------------------------------
 292
 293         protected $mLastQuery = '';
 294
 295         protected $mServer, $mUser, $mPassword, $mConn = null, $mDBname;
 296         protected $mOut, $mOpened = false;
 297
 298         protected $mFailFunction;
 299         protected $mTablePrefix;
 300         protected $mFlags;
 301         protected $mTrxLevel = 0;
 302         protected $mErrorCount = 0;
 303         protected $mLBInfo = array();
 304
 305 #------------------------------------------------------------------------------
 306 # Accessors
 307 #------------------------------------------------------------------------------
 308         # These optionally set a variable and return the previous state
 309
 310         /**
 311          * Fail function, takes a Database as a parameter
 312          * Set to false for default, 1 for ignore errors
 313          */
 314         function failFunction( $function = NULL ) {
 315                 return wfSetVar( $this->mFailFunction, $function );
 316         }
 317
 318         /**
 319          * Output page, used for reporting errors
 320          * FALSE means discard output
 321          */
 322         function setOutputPage( $out ) {
 323                 $this->mOut = $out;
 324         }
 325
 326         /**
 327          * Boolean, controls output of large amounts of debug information
 328          */
 329         function debug( $debug = NULL ) {
 330                 return wfSetBit( $this->mFlags, DBO_DEBUG, $debug );
 331         }
 332
 333         /**
 334          * Turns buffering of SQL result sets on (true) or off (false).
 335          * Default is "on" and it should not be changed without good reasons.
 336          */
 337         function bufferResults( $buffer = NULL ) {
 338                 if ( is_null( $buffer ) ) {
 339                         return !(bool)( $this->mFlags & DBO_NOBUFFER );
 340                 } else {
 341                         return !wfSetBit( $this->mFlags, DBO_NOBUFFER, !$buffer );
 342                 }
 343         }
 344
 345         /**
 346          * Turns on (false) or off (true) the automatic generation and sending
 347          * of a "we're sorry, but there has been a database error" page on
 348          * database errors. Default is on (false). When turned off, the
 349          * code should use lastErrno() and lastError() to handle the
 350          * situation as appropriate.
 351          */
 352         function ignoreErrors( $ignoreErrors = NULL ) {
 353                 return wfSetBit( $this->mFlags, DBO_IGNORE, $ignoreErrors );
 354         }
 355
 356         /**
 357          * The current depth of nested transactions
 358          * @param $level Integer: , default NULL.
 359          */
 360         function trxLevel( $level = NULL ) {
 361                 return wfSetVar( $this->mTrxLevel, $level );
 362         }
 363
 364         /**
 365          * Number of errors logged, only useful when errors are ignored
 366          */
 367         function errorCount( $count = NULL ) {
 368                 return wfSetVar( $this->mErrorCount, $count );
 369         }
 370
 371         /**
 372          * Properties passed down from the server info array of the load balancer
 373          */
 374         function getLBInfo( $name = NULL ) {
 375                 if ( is_null( $name ) ) {
 376                         return $this->mLBInfo;
 377                 } else {
 378                         if ( array_key_exists( $name, $this->mLBInfo ) ) {
 379                                 return $this->mLBInfo[$name];
 380                         } else {
 381                                 return NULL;
 382                         }
 383                 }
 384         }
 385
 386         function setLBInfo( $name, $value = NULL ) {
 387                 if ( is_null( $value ) ) {
 388                         $this->mLBInfo = $name;
 389                 } else {
 390                         $this->mLBInfo[$name] = $value;
 391                 }
 392         }
 393
 394         /**
 395          * Returns true if this database supports (and uses) cascading deletes
 396          */
 397         function cascadingDeletes() {
 398                 return false;
 399         }
 400
 401         /**
 402          * Returns true if this database supports (and uses) triggers (e.g. on the page table)
 403          */
 404         function cleanupTriggers() {
 405                 return false;
 406         }
 407
 408         /**
 409          * Returns true if this database is strict about what can be put into an IP field.
 410          * Specifically, it uses a NULL value instead of an empty string.
 411          */
 412         function strictIPs() {
 413                 return false;
 414         }
 415
 416         /**
 417          * Returns true if this database uses timestamps rather than integers
 418         */
 419         function realTimestamps() {
 420                 return false;
 421         }
 422
 423         /**
 424          * Returns true if this database does an implicit sort when doing GROUP BY
 425          */
 426         function implicitGroupby() {
 427                 return true;
 428         }
 429
 430         /**
 431          * Returns true if this database can do a native search on IP columns
 432          * e.g. this works as expected: .. WHERE rc_ip = '127.42.12.102/32';
 433          */
 434         function searchableIPs() {
 435                 return false;
 436         }
 437
 438         /**#@+
 439          * Get function
 440          */
 441         function lastQuery() { return $this->mLastQuery; }
 442         function isOpen() { return $this->mOpened; }
 443         /**#@-*/
 444
 445         function setFlag( $flag ) {
 446                 $this->mFlags |= $flag;
 447         }
 448
 449         function clearFlag( $flag ) {
 450                 $this->mFlags &= ~$flag;
 451         }
 452
 453         function getFlag( $flag ) {
 454                 return !!($this->mFlags & $flag);
 455         }
 456
 457         /**
 458          * General read-only accessor
 459          */
 460         function getProperty( $name ) {
 461                 return $this->$name;
 462         }
 463
 464 #------------------------------------------------------------------------------
 465 # Other functions
 466 #------------------------------------------------------------------------------
 467
 468         /**@{{
 469          * Constructor.
 470          * @param string $server database server host
 471          * @param string $user database user name
 472          * @param string $password database user password
 473          * @param string $dbname database name
 474          * @param failFunction
 475          * @param $flags
 476          * @param $tablePrefix String: database table prefixes. By default use the prefix gave in LocalSettings.php
 477          */
 478         function __construct( $server = false, $user = false, $password = false, $dbName = false,
 479                 $failFunction = false, $flags = 0, $tablePrefix = 'get from global' ) {
 480
 481                 global $wgOut, $wgDBprefix, $wgCommandLineMode;
 482                 # Can't get a reference if it hasn't been set yet
 483                 if ( !isset( $wgOut ) ) {
 484                         $wgOut = NULL;
 485                 }
 486                 $this->mOut =& $wgOut;
 487
 488                 $this->mFailFunction = $failFunction;
 489                 $this->mFlags = $flags;
 490
 491                 if ( $this->mFlags & DBO_DEFAULT ) {
 492                         if ( $wgCommandLineMode ) {
 493                                 $this->mFlags &= ~DBO_TRX;
 494                         } else {
 495                                 $this->mFlags |= DBO_TRX;
 496                         }
 497                 }
 498
 499                 /*
 500                 // Faster read-only access
 501                 if ( wfReadOnly() ) {
 502                         $this->mFlags |= DBO_PERSISTENT;
 503                         $this->mFlags &= ~DBO_TRX;
 504                 }*/
 505
 506                 /** Get the default table prefix*/
 507                 if ( $tablePrefix == 'get from global' ) {
 508                         $this->mTablePrefix = $wgDBprefix;
 509                 } else {
 510                         $this->mTablePrefix = $tablePrefix;
 511                 }
 512
 513                 if ( $server ) {
 514                         $this->open( $server, $user, $password, $dbName );
 515                 }
 516         }
 517
 518         /**
 519          * @static
 520          * @param failFunction
 521          * @param $flags
 522          */
 523         static function newFromParams( $server, $user, $password, $dbName, $failFunction = false, $flags = 0 )
 524         {
 525                 return new Database( $server, $user, $password, $dbName, $failFunction, $flags );
 526         }
 527
 528         /**
 529          * Usually aborts on failure
 530          * If the failFunction is set to a non-zero integer, returns success
 531          */
 532         function open( $server, $user, $password, $dbName ) {
 533                 global $wguname;
 534                 wfProfileIn( __METHOD__ );
 535
 536                 # Test for missing mysql.so
 537                 # First try to load it
 538                 if (!@extension_loaded('mysql')) {
 539                         @dl('mysql.so');
 540                 }
 541
 542                 # Fail now
 543                 # Otherwise we get a suppressed fatal error, which is very hard to track down
 544                 if ( !function_exists( 'mysql_connect' ) ) {
 545                         throw new DBConnectionError( $this, "MySQL functions missing, have you compiled PHP with the --with-mysql option?\n" );
 546                 }
 547
 548                 $this->close();
 549                 $this->mServer = $server;
 550                 $this->mUser = $user;
 551                 $this->mPassword = $password;
 552                 $this->mDBname = $dbName;
 553
 554                 $success = false;
 555
 556                 wfProfileIn("dbconnect-$server");
 557
 558                 # LIVE PATCH by Tim, ask Domas for why: retry loop
 559                 $this->mConn = false;
 560                 $max = 3;
 561                 for ( $i = 0; $i < $max && !$this->mConn; $i++ ) {
 562                         if ( $i > 1 ) {
 563                                 usleep( 1000 );
 564                         }
 565                         if ( $this->mFlags & DBO_PERSISTENT ) {
 566                                 @/**/$this->mConn = mysql_pconnect( $server, $user, $password );
 567                         } else {
 568                                 # Create a new connection...
 569                                 @/**/$this->mConn = mysql_connect( $server, $user, $password, true );
 570                         }
 571                         if ($this->mConn === false) {
 572                                 $iplus = $i + 1;
 573                                 #wfLogDBError("Connect loop error $iplus of $max ($server): " . mysql_errno() . " - " . mysql_error()."\n");
 574                         }
 575                 }
 576
 577                 wfProfileOut("dbconnect-$server");
 578
 579                 if ( $dbName != '' ) {
 580                         if ( $this->mConn !== false ) {
 581                                 $success = @/**/mysql_select_db( $dbName, $this->mConn );
 582                                 if ( !$success ) {
 583                                         $error = "Error selecting database $dbName on server {$this->mServer} " .
 584                                                 "from client host {$wguname['nodename']}\n";
 585                                         wfLogDBError(" Error selecting database $dbName on server {$this->mServer} \n");
 586                                         wfDebug( $error );
 587                                 }
 588                         } else {
 589                                 wfDebug( "DB connection error\n" );
 590                                 wfDebug( "Server: $server, User: $user, Password: " .
 591                                         substr( $password, 0, 3 ) . "..., error: " . mysql_error() . "\n" );
 592                                 $success = false;
 593                         }
 594                 } else {
 595                         # Delay USE query
 596                         $success = (bool)$this->mConn;
 597                 }
 598
 599                 if ( $success ) {
 600                         global $wgDBmysql5;
 601                         if( $wgDBmysql5 ) {
 602                                 // Tell the server we're communicating with it in UTF-8.
 603                                 // This may engage various charset conversions.
 604                                 $this->query( 'SET NAMES utf8' );
 605                         }
 606                 } else {
 607                         $this->reportConnectionError();
 608                 }
 609
 610                 $this->mOpened = $success;
 611                 wfProfileOut( __METHOD__ );
 612                 return $success;
 613         }
 614         /**@}}*/
 615
 616         /**
 617          * Closes a database connection.
 618          * if it is open : commits any open transactions
 619          *
 620          * @return bool operation success. true if already closed.
 621          */
 622         function close()
 623         {
 624                 $this->mOpened = false;
 625                 if ( $this->mConn ) {
 626                         if ( $this->trxLevel() ) {
 627                                 $this->immediateCommit();
 628                         }
 629                         return mysql_close( $this->mConn );
 630                 } else {
 631                         return true;
 632                 }
 633         }
 634
 635         /**
 636          * @param string $error fallback error message, used if none is given by MySQL
 637          */
 638         function reportConnectionError( $error = 'Unknown error' ) {
 639                 $myError = $this->lastError();
 640                 if ( $myError ) {
 641                         $error = $myError;
 642                 }
 643
 644                 if ( $this->mFailFunction ) {
 645                         # Legacy error handling method
 646                         if ( !is_int( $this->mFailFunction ) ) {
 647                                 $ff = $this->mFailFunction;
 648                                 $ff( $this, $error );
 649                         }
 650                 } else {
 651                         # New method
 652                         wfLogDBError( "Connection error: $error\n" );
 653                         throw new DBConnectionError( $this, $error );
 654                 }
 655         }
 656
 657         /**
 658          * Usually aborts on failure.  If errors are explicitly ignored, returns success.
 659          *
 660          * @param  $sql        String: SQL query
 661          * @param  $fname      String: Name of the calling function, for profiling/SHOW PROCESSLIST comment (you can use __METHOD__ or add some extra info)
 662          * @param  $tempIgnore Bool:   Whether to avoid throwing an exception on errors... maybe best to catch the exception instead?
 663          * @return Result object to feed to fetchObject, fetchRow, ...; or false on failure if $tempIgnore set
 664          * @throws DBQueryError Thrown when the database returns an error of any kind
 665          */
 666         public function query( $sql, $fname = '', $tempIgnore = false ) {
 667                 global $wgProfiling;
 668
 669                 if ( $wgProfiling ) {
 670                         # generalizeSQL will probably cut down the query to reasonable
 671                         # logging size most of the time. The substr is really just a sanity check.
 672
 673                         # Who's been wasting my precious column space? -- TS
 674                         #$profName = 'query: ' . $fname . ' ' . substr( Database::generalizeSQL( $sql ), 0, 255 );
 675
 676                         if ( is_null( $this->getLBInfo( 'master' ) ) ) {
 677                                 $queryProf = 'query: ' . substr( Database::generalizeSQL( $sql ), 0, 255 );
 678                                 $totalProf = 'Database::query';
 679                         } else {
 680                                 $queryProf = 'query-m: ' . substr( Database::generalizeSQL( $sql ), 0, 255 );
 681                                 $totalProf = 'Database::query-master';
 682                         }
 683                         wfProfileIn( $totalProf );
 684                         wfProfileIn( $queryProf );
 685                 }
 686
 687                 $this->mLastQuery = $sql;
 688
 689                 # Add a comment for easy SHOW PROCESSLIST interpretation
 690                 if ( $fname ) {
 691                         $commentedSql = preg_replace('/\s/', " /* $fname */ ", $sql, 1);
 692                 } else {
 693                         $commentedSql = $sql;
 694                 }
 695
 696                 # If DBO_TRX is set, start a transaction
 697                 if ( ( $this->mFlags & DBO_TRX ) && !$this->trxLevel() &&
 698                         $sql != 'BEGIN' && $sql != 'COMMIT' && $sql != 'ROLLBACK'
 699                 ) {
 700                         $this->begin();
 701                 }
 702
 703                 if ( $this->debug() ) {
 704                         $sqlx = substr( $commentedSql, 0, 500 );
 705                         $sqlx = strtr( $sqlx, "\t\n", '  ' );
 706                         wfDebug( "SQL: $sqlx\n" );
 707                 }
 708
 709                 # Do the query and handle errors
 710                 $ret = $this->doQuery( $commentedSql );
 711
 712                 # Try reconnecting if the connection was lost
 713                 if ( false === $ret && ( $this->lastErrno() == 2013 || $this->lastErrno() == 2006 ) ) {
 714                         # Transaction is gone, like it or not
 715                         $this->mTrxLevel = 0;
 716                         wfDebug( "Connection lost, reconnecting...\n" );
 717                         if ( $this->ping() ) {
 718                                 wfDebug( "Reconnected\n" );
 719                                 $sqlx = substr( $commentedSql, 0, 500 );
 720                                 $sqlx = strtr( $sqlx, "\t\n", '  ' );
 721                                 global $wgRequestTime;
 722                                 $elapsed = round( microtime(true) - $wgRequestTime, 3 );
 723                                 wfLogDBError( "Connection lost and reconnected after {$elapsed}s, query: $sqlx\n" );
 724                                 $ret = $this->doQuery( $commentedSql );
 725                         } else {
 726                                 wfDebug( "Failed\n" );
 727                         }
 728                 }
 729
 730                 if ( false === $ret ) {
 731                         $this->reportQueryError( $this->lastError(), $this->lastErrno(), $sql, $fname, $tempIgnore );
 732                 }
 733
 734                 if ( $wgProfiling ) {
 735                         wfProfileOut( $queryProf );
 736                         wfProfileOut( $totalProf );
 737                 }
 738                 return $ret;
 739         }
 740
 741         /**
 742          * The DBMS-dependent part of query()
 743          * @param  $sql String: SQL query.
 744          * @return Result object to feed to fetchObject, fetchRow, ...; or false on failure
 745          * @access private
 746          */
 747         /*private*/ function doQuery( $sql ) {
 748                 if( $this->bufferResults() ) {
 749                         $ret = mysql_query( $sql, $this->mConn );
 750                 } else {
 751                         $ret = mysql_unbuffered_query( $sql, $this->mConn );
 752                 }
 753                 return $ret;
 754         }
 755
 756         /**
 757          * @param $error
 758          * @param $errno
 759          * @param $sql
 760          * @param string $fname
 761          * @param bool $tempIgnore
 762          */
 763         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 764                 global $wgCommandLineMode;
 765                 # Ignore errors during error handling to avoid infinite recursion
 766                 $ignore = $this->ignoreErrors( true );
 767                 ++$this->mErrorCount;
 768
 769                 if( $ignore || $tempIgnore ) {
 770                         wfDebug("SQL ERROR (ignored): $error\n");
 771                         $this->ignoreErrors( $ignore );
 772                 } else {
 773                         $sql1line = str_replace( "\n", "\\n", $sql );
 774                         wfLogDBError("$fname\t{$this->mServer}\t$errno\t$error\t$sql1line\n");
 775                         wfDebug("SQL ERROR: " . $error . "\n");
 776                         throw new DBQueryError( $this, $error, $errno, $sql, $fname );
 777                 }
 778         }
 779
 780
 781         /**
 782          * Intended to be compatible with the PEAR::DB wrapper functions.
 783          * http://pear.php.net/manual/en/package.database.db.intro-execute.php
 784          *
 785          * ? = scalar value, quoted as necessary
 786          * ! = raw SQL bit (a function for instance)
 787          * & = filename; reads the file and inserts as a blob
 788          *     (we don't use this though...)
 789          */
 790         function prepare( $sql, $func = 'Database::prepare' ) {
 791                 /* MySQL doesn't support prepared statements (yet), so just
 792                    pack up the query for reference. We'll manually replace
 793                    the bits later. */
 794                 return array( 'query' => $sql, 'func' => $func );
 795         }
 796
 797         function freePrepared( $prepared ) {
 798                 /* No-op for MySQL */
 799         }
 800
 801         /**
 802          * Execute a prepared query with the various arguments
 803          * @param string $prepared the prepared sql
 804          * @param mixed $args Either an array here, or put scalars as varargs
 805          */
 806         function execute( $prepared, $args = null ) {
 807                 if( !is_array( $args ) ) {
 808                         # Pull the var args
 809                         $args = func_get_args();
 810                         array_shift( $args );
 811                 }
 812                 $sql = $this->fillPrepared( $prepared['query'], $args );
 813                 return $this->query( $sql, $prepared['func'] );
 814         }
 815
 816         /**
 817          * Prepare & execute an SQL statement, quoting and inserting arguments
 818          * in the appropriate places.
 819          * @param string $query
 820          * @param string $args ...
 821          */
 822         function safeQuery( $query, $args = null ) {
 823                 $prepared = $this->prepare( $query, 'Database::safeQuery' );
 824                 if( !is_array( $args ) ) {
 825                         # Pull the var args
 826                         $args = func_get_args();
 827                         array_shift( $args );
 828                 }
 829                 $retval = $this->execute( $prepared, $args );
 830                 $this->freePrepared( $prepared );
 831                 return $retval;
 832         }
 833
 834         /**
 835          * For faking prepared SQL statements on DBs that don't support
 836          * it directly.
 837          * @param string $preparedSql - a 'preparable' SQL statement
 838          * @param array $args - array of arguments to fill it with
 839          * @return string executable SQL
 840          */
 841         function fillPrepared( $preparedQuery, $args ) {
 842                 reset( $args );
 843                 $this->preparedArgs =& $args;
 844                 return preg_replace_callback( '/(\\\\[?!&]|[?!&])/',
 845                         array( &$this, 'fillPreparedArg' ), $preparedQuery );
 846         }
 847
 848         /**
 849          * preg_callback func for fillPrepared()
 850          * The arguments should be in $this->preparedArgs and must not be touched
 851          * while we're doing this.
 852          *
 853          * @param array $matches
 854          * @return string
 855          * @private
 856          */
 857         function fillPreparedArg( $matches ) {
 858                 switch( $matches[1] ) {
 859                         case '\\?': return '?';
 860                         case '\\!': return '!';
 861                         case '\\&': return '&';
 862                 }
 863                 list( /* $n */ , $arg ) = each( $this->preparedArgs );
 864                 switch( $matches[1] ) {
 865                         case '?': return $this->addQuotes( $arg );
 866                         case '!': return $arg;
 867                         case '&':
 868                                 # return $this->addQuotes( file_get_contents( $arg ) );
 869                                 throw new DBUnexpectedError( $this, '& mode is not implemented. If it\'s really needed, uncomment the line above.' );
 870                         default:
 871                                 throw new DBUnexpectedError( $this, 'Received invalid match. This should never happen!' );
 872                 }
 873         }
 874
 875         /**#@+
 876          * @param mixed $res A SQL result
 877          */
 878         /**
 879          * Free a result object
 880          */
 881         function freeResult( $res ) {
 882                 if ( !@/**/mysql_free_result( $res ) ) {
 883                         throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
 884                 }
 885         }
 886
 887         /**
 888          * Fetch the next row from the given result object, in object form.
 889          * Fields can be retrieved with $row->fieldname, with fields acting like
 890          * member variables.
 891          *
 892          * @param $res SQL result object as returned from Database::query(), etc.
 893          * @return MySQL row object
 894          * @throws DBUnexpectedError Thrown if the database returns an error
 895          */
 896         function fetchObject( $res ) {
 897                 @/**/$row = mysql_fetch_object( $res );
 898                 if( $this->lastErrno() ) {
 899                         throw new DBUnexpectedError( $this, 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() ) );
 900                 }
 901                 return $row;
 902         }
 903
 904         /**
 905          * Fetch the next row from the given result object, in associative array
 906          * form.  Fields are retrieved with $row['fieldname'].
 907          *
 908          * @param $res SQL result object as returned from Database::query(), etc.
 909          * @return MySQL row object
 910          * @throws DBUnexpectedError Thrown if the database returns an error
 911          */
 912         function fetchRow( $res ) {
 913                 @/**/$row = mysql_fetch_array( $res );
 914                 if ( $this->lastErrno() ) {
 915                         throw new DBUnexpectedError( $this, 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() ) );
 916                 }
 917                 return $row;
 918         }
 919
 920         /**
 921          * Get the number of rows in a result object
 922          */
 923         function numRows( $res ) {
 924                 @/**/$n = mysql_num_rows( $res );
 925                 if( $this->lastErrno() ) {
 926                         throw new DBUnexpectedError( $this, 'Error in numRows(): ' . htmlspecialchars( $this->lastError() ) );
 927                 }
 928                 return $n;
 929         }
 930
 931         /**
 932          * Get the number of fields in a result object
 933          * See documentation for mysql_num_fields()
 934          */
 935         function numFields( $res ) { return mysql_num_fields( $res ); }
 936
 937         /**
 938          * Get a field name in a result object
 939          * See documentation for mysql_field_name():
 940          * http://www.php.net/mysql_field_name
 941          */
 942         function fieldName( $res, $n ) { return mysql_field_name( $res, $n ); }
 943
 944         /**
 945          * Get the inserted value of an auto-increment row
 946          *
 947          * The value inserted should be fetched from nextSequenceValue()
 948          *
 949          * Example:
 950          * $id = $dbw->nextSequenceValue('page_page_id_seq');
 951          * $dbw->insert('page',array('page_id' => $id));
 952          * $id = $dbw->insertId();
 953          */
 954         function insertId() { return mysql_insert_id( $this->mConn ); }
 955
 956         /**
 957          * Change the position of the cursor in a result object
 958          * See mysql_data_seek()
 959          */
 960         function dataSeek( $res, $row ) { return mysql_data_seek( $res, $row ); }
 961
 962         /**
 963          * Get the last error number
 964          * See mysql_errno()
 965          */
 966         function lastErrno() {
 967                 if ( $this->mConn ) {
 968                         return mysql_errno( $this->mConn );
 969                 } else {
 970                         return mysql_errno();
 971                 }
 972         }
 973
 974         /**
 975          * Get a description of the last error
 976          * See mysql_error() for more details
 977          */
 978         function lastError() {
 979                 if ( $this->mConn ) {
 980                         # Even if it's non-zero, it can still be invalid
 981                         wfSuppressWarnings();
 982                         $error = mysql_error( $this->mConn );
 983                         if ( !$error ) {
 984                                 $error = mysql_error();
 985                         }
 986                         wfRestoreWarnings();
 987                 } else {
 988                         $error = mysql_error();
 989                 }
 990                 if( $error ) {
 991                         $error .= ' (' . $this->mServer . ')';
 992                 }
 993                 return $error;
 994         }
 995         /**
 996          * Get the number of rows affected by the last write query
 997          * See mysql_affected_rows() for more details
 998          */
 999         function affectedRows() { return mysql_affected_rows( $this->mConn ); }
1000         /**#@-*/ // end of template : @param $result
1001
1002         /**
1003          * Simple UPDATE wrapper
1004          * Usually aborts on failure
1005          * If errors are explicitly ignored, returns success
1006          *
1007          * This function exists for historical reasons, Database::update() has a more standard
1008          * calling convention and feature set
1009          */
1010         function set( $table, $var, $value, $cond, $fname = 'Database::set' )
1011         {
1012                 $table = $this->tableName( $table );
1013                 $sql = "UPDATE $table SET $var = '" .
1014                   $this->strencode( $value ) . "' WHERE ($cond)";
1015                 return (bool)$this->query( $sql, $fname );
1016         }
1017
1018         /**
1019          * Simple SELECT wrapper, returns a single field, input must be encoded
1020          * Usually aborts on failure
1021          * If errors are explicitly ignored, returns FALSE on failure
1022          */
1023         function selectField( $table, $var, $cond='', $fname = 'Database::selectField', $options = array() ) {
1024                 if ( !is_array( $options ) ) {
1025                         $options = array( $options );
1026                 }
1027                 $options['LIMIT'] = 1;
1028
1029                 $res = $this->select( $table, $var, $cond, $fname, $options );
1030                 if ( $res === false || !$this->numRows( $res ) ) {
1031                         return false;
1032                 }
1033                 $row = $this->fetchRow( $res );
1034                 if ( $row !== false ) {
1035                         $this->freeResult( $res );
1036                         return $row[0];
1037                 } else {
1038                         return false;
1039                 }
1040         }
1041
1042         /**
1043          * Returns an optional USE INDEX clause to go after the table, and a
1044          * string to go at the end of the query
1045          *
1046          * @private
1047          *
1048          * @param array $options an associative array of options to be turned into
1049          *              an SQL query, valid keys are listed in the function.
1050          * @return array
1051          */
1052         function makeSelectOptions( $options ) {
1053                 $preLimitTail = $postLimitTail = '';
1054                 $startOpts = '';
1055
1056                 $noKeyOptions = array();
1057                 foreach ( $options as $key => $option ) {
1058                         if ( is_numeric( $key ) ) {
1059                                 $noKeyOptions[$option] = true;
1060                         }
1061                 }
1062
1063                 if ( isset( $options['GROUP BY'] ) ) $preLimitTail .= " GROUP BY {$options['GROUP BY']}";
1064                 if ( isset( $options['ORDER BY'] ) ) $preLimitTail .= " ORDER BY {$options['ORDER BY']}";
1065
1066                 //if (isset($options['LIMIT'])) {
1067                 //      $tailOpts .= $this->limitResult('', $options['LIMIT'],
1068                 //              isset($options['OFFSET']) ? $options['OFFSET']
1069                 //              : false);
1070                 //}
1071
1072                 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) $postLimitTail .= ' FOR UPDATE';
1073                 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) $postLimitTail .= ' LOCK IN SHARE MODE';
1074                 if ( isset( $noKeyOptions['DISTINCT'] ) && isset( $noKeyOptions['DISTINCTROW'] ) ) $startOpts .= 'DISTINCT';
1075
1076                 # Various MySQL extensions
1077                 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) $startOpts .= ' /*! STRAIGHT_JOIN */';
1078                 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) $startOpts .= ' HIGH_PRIORITY';
1079                 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) $startOpts .= ' SQL_BIG_RESULT';
1080                 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) $startOpts .= ' SQL_BUFFER_RESULT';
1081                 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) $startOpts .= ' SQL_SMALL_RESULT';
1082                 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) $startOpts .= ' SQL_CALC_FOUND_ROWS';
1083                 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) $startOpts .= ' SQL_CACHE';
1084                 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) $startOpts .= ' SQL_NO_CACHE';
1085
1086                 if ( isset( $options['USE INDEX'] ) && ! is_array( $options['USE INDEX'] ) ) {
1087                         $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1088                 } else {
1089                         $useIndex = '';
1090                 }
1091
1092                 return array( $startOpts, $useIndex, $preLimitTail, $postLimitTail );
1093         }
1094
1095         /**
1096          * SELECT wrapper
1097          *
1098          * @param mixed  $table   Array or string, table name(s) (prefix auto-added)
1099          * @param mixed  $vars    Array or string, field name(s) to be retrieved
1100          * @param mixed  $conds   Array or string, condition(s) for WHERE
1101          * @param string $fname   Calling function name (use __METHOD__) for logs/profiling
1102          * @param array  $options Associative array of options (e.g. array('GROUP BY' => 'page_title')),
1103          *                        see Database::makeSelectOptions code for list of supported stuff
1104          * @return mixed Database result resource (feed to Database::fetchObject or whatever), or false on failure
1105          */
1106         function select( $table, $vars, $conds='', $fname = 'Database::select', $options = array() )
1107         {
1108                 if( is_array( $vars ) ) {
1109                         $vars = implode( ',', $vars );
1110                 }
1111                 if( !is_array( $options ) ) {
1112                         $options = array( $options );
1113                 }
1114                 if( is_array( $table ) ) {
1115                         if ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1116                                 $from = ' FROM ' . $this->tableNamesWithUseIndex( $table, $options['USE INDEX'] );
1117                         else
1118                                 $from = ' FROM ' . implode( ',', array_map( array( &$this, 'tableName' ), $table ) );
1119                 } elseif ($table!='') {
1120                         if ($table{0}==' ') {
1121                                 $from = ' FROM ' . $table;
1122                         } else {
1123                                 $from = ' FROM ' . $this->tableName( $table );
1124                         }
1125                 } else {
1126                         $from = '';
1127                 }
1128
1129                 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail ) = $this->makeSelectOptions( $options );
1130
1131                 if( !empty( $conds ) ) {
1132                         if ( is_array( $conds ) ) {
1133                                 $conds = $this->makeList( $conds, LIST_AND );
1134                         }
1135                         $sql = "SELECT $startOpts $vars $from $useIndex WHERE $conds $preLimitTail";
1136                 } else {
1137                         $sql = "SELECT $startOpts $vars $from $useIndex $preLimitTail";
1138                 }
1139
1140                 if (isset($options['LIMIT']))
1141                         $sql = $this->limitResult($sql, $options['LIMIT'],
1142                                 isset($options['OFFSET']) ? $options['OFFSET'] : false);
1143                 $sql = "$sql $postLimitTail";
1144
1145                 if (isset($options['EXPLAIN'])) {
1146                         $sql = 'EXPLAIN ' . $sql;
1147                 }
1148
1149                 return $this->query( $sql, $fname );
1150         }
1151
1152         /**
1153          * Single row SELECT wrapper
1154          * Aborts or returns FALSE on error
1155          *
1156          * $vars: the selected variables
1157          * $conds: a condition map, terms are ANDed together.
1158          *   Items with numeric keys are taken to be literal conditions
1159          * Takes an array of selected variables, and a condition map, which is ANDed
1160          * e.g: selectRow( "page", array( "page_id" ), array( "page_namespace" =>
1161          * NS_MAIN, "page_title" => "Astronomy" ) )   would return an object where
1162          * $obj- >page_id is the ID of the Astronomy article
1163          *
1164          * @todo migrate documentation to phpdocumentor format
1165          */
1166         function selectRow( $table, $vars, $conds, $fname = 'Database::selectRow', $options = array() ) {
1167                 $options['LIMIT'] = 1;
1168                 $res = $this->select( $table, $vars, $conds, $fname, $options );
1169                 if ( $res === false )
1170                         return false;
1171                 if ( !$this->numRows($res) ) {
1172                         $this->freeResult($res);
1173                         return false;
1174                 }
1175                 $obj = $this->fetchObject( $res );
1176                 $this->freeResult( $res );
1177                 return $obj;
1178
1179         }
1180
1181         /**
1182          * Estimate rows in dataset
1183          * Returns estimated count, based on EXPLAIN output
1184          * Takes same arguments as Database::select()
1185          */
1186
1187         function estimateRowCount( $table, $vars='*', $conds='', $fname = 'Database::estimateRowCount', $options = array() ) {
1188                 $options['EXPLAIN']=true;
1189                 $res = $this->select ($table, $vars, $conds, $fname, $options );
1190                 if ( $res === false )
1191                         return false;
1192                 if (!$this->numRows($res)) {
1193                         $this->freeResult($res);
1194                         return 0;
1195                 }
1196
1197                 $rows=1;
1198
1199                 while( $plan = $this->fetchObject( $res ) ) {
1200                         $rows *= ($plan->rows > 0)?$plan->rows:1; // avoid resetting to zero
1201                 }
1202
1203                 $this->freeResult($res);
1204                 return $rows;
1205         }
1206
1207
1208         /**
1209          * Removes most variables from an SQL query and replaces them with X or N for numbers.
1210          * It's only slightly flawed. Don't use for anything important.
1211          *
1212          * @param string $sql A SQL Query
1213          * @static
1214          */
1215         static function generalizeSQL( $sql ) {
1216                 # This does the same as the regexp below would do, but in such a way
1217                 # as to avoid crashing php on some large strings.
1218                 # $sql = preg_replace ( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql);
1219
1220                 $sql = str_replace ( "\\\\", '', $sql);
1221                 $sql = str_replace ( "\\'", '', $sql);
1222                 $sql = str_replace ( "\\\"", '', $sql);
1223                 $sql = preg_replace ("/'.*'/s", "'X'", $sql);
1224                 $sql = preg_replace ('/".*"/s', "'X'", $sql);
1225
1226                 # All newlines, tabs, etc replaced by single space
1227                 $sql = preg_replace ( '/\s+/', ' ', $sql);
1228
1229                 # All numbers => N
1230                 $sql = preg_replace ('/-?[0-9]+/s', 'N', $sql);
1231
1232                 return $sql;
1233         }
1234
1235         /**
1236          * Determines whether a field exists in a table
1237          * Usually aborts on failure
1238          * If errors are explicitly ignored, returns NULL on failure
1239          */
1240         function fieldExists( $table, $field, $fname = 'Database::fieldExists' ) {
1241                 $table = $this->tableName( $table );
1242                 $res = $this->query( 'DESCRIBE '.$table, $fname );
1243                 if ( !$res ) {
1244                         return NULL;
1245                 }
1246
1247                 $found = false;
1248
1249                 while ( $row = $this->fetchObject( $res ) ) {
1250                         if ( $row->Field == $field ) {
1251                                 $found = true;
1252                                 break;
1253                         }
1254                 }
1255                 return $found;
1256         }
1257
1258         /**
1259          * Determines whether an index exists
1260          * Usually aborts on failure
1261          * If errors are explicitly ignored, returns NULL on failure
1262          */
1263         function indexExists( $table, $index, $fname = 'Database::indexExists' ) {
1264                 $info = $this->indexInfo( $table, $index, $fname );
1265                 if ( is_null( $info ) ) {
1266                         return NULL;
1267                 } else {
1268                         return $info !== false;
1269                 }
1270         }
1271
1272
1273         /**
1274          * Get information about an index into an object
1275          * Returns false if the index does not exist
1276          */
1277         function indexInfo( $table, $index, $fname = 'Database::indexInfo' ) {
1278                 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
1279                 # SHOW INDEX should work for 3.x and up:
1280                 # http://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
1281                 $table = $this->tableName( $table );
1282                 $sql = 'SHOW INDEX FROM '.$table;
1283                 $res = $this->query( $sql, $fname );
1284                 if ( !$res ) {
1285                         return NULL;
1286                 }
1287
1288                 $result = array();
1289                 while ( $row = $this->fetchObject( $res ) ) {
1290                         if ( $row->Key_name == $index ) {
1291                                 $result[] = $row;
1292                         }
1293                 }
1294                 $this->freeResult($res);
1295
1296                 return empty($result) ? false : $result;
1297         }
1298
1299         /**
1300          * Query whether a given table exists
1301          */
1302         function tableExists( $table ) {
1303                 $table = $this->tableName( $table );
1304                 $old = $this->ignoreErrors( true );
1305                 $res = $this->query( "SELECT 1 FROM $table LIMIT 1" );
1306                 $this->ignoreErrors( $old );
1307                 if( $res ) {
1308                         $this->freeResult( $res );
1309                         return true;
1310                 } else {
1311                         return false;
1312                 }
1313         }
1314
1315         /**
1316          * mysql_fetch_field() wrapper
1317          * Returns false if the field doesn't exist
1318          *
1319          * @param $table
1320          * @param $field
1321          */
1322         function fieldInfo( $table, $field ) {
1323                 $table = $this->tableName( $table );
1324                 $res = $this->query( "SELECT * FROM $table LIMIT 1" );
1325                 $n = mysql_num_fields( $res );
1326                 for( $i = 0; $i < $n; $i++ ) {
1327                         $meta = mysql_fetch_field( $res, $i );
1328                         if( $field == $meta->name ) {
1329                                 return new MySQLField($meta);
1330                         }
1331                 }
1332                 return false;
1333         }
1334
1335         /**
1336          * mysql_field_type() wrapper
1337          */
1338         function fieldType( $res, $index ) {
1339                 return mysql_field_type( $res, $index );
1340         }
1341
1342         /**
1343          * Determines if a given index is unique
1344          */
1345         function indexUnique( $table, $index ) {
1346                 $indexInfo = $this->indexInfo( $table, $index );
1347                 if ( !$indexInfo ) {
1348                         return NULL;
1349                 }
1350                 return !$indexInfo[0]->Non_unique;
1351         }
1352
1353         /**
1354          * INSERT wrapper, inserts an array into a table
1355          *
1356          * $a may be a single associative array, or an array of these with numeric keys, for
1357          * multi-row insert.
1358          *
1359          * Usually aborts on failure
1360          * If errors are explicitly ignored, returns success
1361          */
1362         function insert( $table, $a, $fname = 'Database::insert', $options = array() ) {
1363                 # No rows to insert, easy just return now
1364                 if ( !count( $a ) ) {
1365                         return true;
1366                 }
1367
1368                 $table = $this->tableName( $table );
1369                 if ( !is_array( $options ) ) {
1370                         $options = array( $options );
1371                 }
1372                 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
1373                         $multi = true;
1374                         $keys = array_keys( $a[0] );
1375                 } else {
1376                         $multi = false;
1377                         $keys = array_keys( $a );
1378                 }
1379
1380                 $sql = 'INSERT ' . implode( ' ', $options ) .
1381                         " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
1382
1383                 if ( $multi ) {
1384                         $first = true;
1385                         foreach ( $a as $row ) {
1386                                 if ( $first ) {
1387                                         $first = false;
1388                                 } else {
1389                                         $sql .= ',';
1390                                 }
1391                                 $sql .= '(' . $this->makeList( $row ) . ')';
1392                         }
1393                 } else {
1394                         $sql .= '(' . $this->makeList( $a ) . ')';
1395                 }
1396                 return (bool)$this->query( $sql, $fname );
1397         }
1398
1399         /**
1400          * Make UPDATE options for the Database::update function
1401          *
1402          * @private
1403          * @param array $options The options passed to Database::update
1404          * @return string
1405          */
1406         function makeUpdateOptions( $options ) {
1407                 if( !is_array( $options ) ) {
1408                         $options = array( $options );
1409                 }
1410                 $opts = array();
1411                 if ( in_array( 'LOW_PRIORITY', $options ) )
1412                         $opts[] = $this->lowPriorityOption();
1413                 if ( in_array( 'IGNORE', $options ) )
1414                         $opts[] = 'IGNORE';
1415                 return implode(' ', $opts);
1416         }
1417
1418         /**
1419          * UPDATE wrapper, takes a condition array and a SET array
1420          *
1421          * @param string $table  The table to UPDATE
1422          * @param array  $values An array of values to SET
1423          * @param array  $conds  An array of conditions (WHERE). Use '*' to update all rows.
1424          * @param string $fname  The Class::Function calling this function
1425          *                       (for the log)
1426          * @param array  $options An array of UPDATE options, can be one or
1427          *                        more of IGNORE, LOW_PRIORITY
1428          */
1429         function update( $table, $values, $conds, $fname = 'Database::update', $options = array() ) {
1430                 $table = $this->tableName( $table );
1431                 $opts = $this->makeUpdateOptions( $options );
1432                 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, LIST_SET );
1433                 if ( $conds != '*' ) {
1434                         $sql .= " WHERE " . $this->makeList( $conds, LIST_AND );
1435                 }
1436                 $this->query( $sql, $fname );
1437         }
1438
1439         /**
1440          * Makes an encoded list of strings from an array
1441          * $mode:
1442          *        LIST_COMMA         - comma separated, no field names
1443          *        LIST_AND           - ANDed WHERE clause (without the WHERE)
1444          *        LIST_OR            - ORed WHERE clause (without the WHERE)
1445          *        LIST_SET           - comma separated with field names, like a SET clause
1446          *        LIST_NAMES         - comma separated field names
1447          */
1448         function makeList( $a, $mode = LIST_COMMA ) {
1449                 if ( !is_array( $a ) ) {
1450                         throw new DBUnexpectedError( $this, 'Database::makeList called with incorrect parameters' );
1451                 }
1452
1453                 $first = true;
1454                 $list = '';
1455                 foreach ( $a as $field => $value ) {
1456                         if ( !$first ) {
1457                                 if ( $mode == LIST_AND ) {
1458                                         $list .= ' AND ';
1459                                 } elseif($mode == LIST_OR) {
1460                                         $list .= ' OR ';
1461                                 } else {
1462                                         $list .= ',';
1463                                 }
1464                         } else {
1465                                 $first = false;
1466                         }
1467                         if ( ($mode == LIST_AND || $mode == LIST_OR) && is_numeric( $field ) ) {
1468                                 $list .= "($value)";
1469                         } elseif ( ($mode == LIST_SET) && is_numeric( $field ) ) {
1470                                 $list .= "$value";
1471                         } elseif ( ($mode == LIST_AND || $mode == LIST_OR) && is_array ($value) ) {
1472                                 $list .= $field." IN (".$this->makeList($value).") ";
1473                         } else {
1474                                 if ( $mode == LIST_AND || $mode == LIST_OR || $mode == LIST_SET ) {
1475                                         $list .= "$field = ";
1476                                 }
1477                                 $list .= $mode == LIST_NAMES ? $value : $this->addQuotes( $value );
1478                         }
1479                 }
1480                 return $list;
1481         }
1482
1483         /**
1484          * Change the current database
1485          */
1486         function selectDB( $db ) {
1487                 $this->mDBname = $db;
1488                 return mysql_select_db( $db, $this->mConn );
1489         }
1490
1491         /**
1492          * Format a table name ready for use in constructing an SQL query
1493          *
1494          * This does two important things: it quotes table names which as necessary,
1495          * and it adds a table prefix if there is one.
1496          *
1497          * All functions of this object which require a table name call this function
1498          * themselves. Pass the canonical name to such functions. This is only needed
1499          * when calling query() directly.
1500          *
1501          * @param string $name database table name
1502          */
1503         function tableName( $name ) {
1504                 global $wgSharedDB;
1505                 # Skip quoted literals
1506                 if ( $name{0} != '`' ) {
1507                         if ( $this->mTablePrefix !== '' &&  strpos( '.', $name ) === false ) {
1508                                 $name = "{$this->mTablePrefix}$name";
1509                         }
1510                         if ( isset( $wgSharedDB ) && "{$this->mTablePrefix}user" == $name ) {
1511                                 $name = "`$wgSharedDB`.`$name`";
1512                         } else {
1513                                 # Standard quoting
1514                                 $name = "`$name`";
1515                         }
1516                 }
1517                 return $name;
1518         }
1519
1520         /**
1521          * Fetch a number of table names into an array
1522          * This is handy when you need to construct SQL for joins
1523          *
1524          * Example:
1525          * extract($dbr->tableNames('user','watchlist'));
1526          * $sql = "SELECT wl_namespace,wl_title FROM $watchlist,$user
1527          *         WHERE wl_user=user_id AND wl_user=$nameWithQuotes";
1528          */
1529         public function tableNames() {
1530                 $inArray = func_get_args();
1531                 $retVal = array();
1532                 foreach ( $inArray as $name ) {
1533                         $retVal[$name] = $this->tableName( $name );
1534                 }
1535                 return $retVal;
1536         }
1537
1538         /**
1539          * Fetch a number of table names into an zero-indexed numerical array
1540          * This is handy when you need to construct SQL for joins
1541          *
1542          * Example:
1543          * list( $user, $watchlist ) = $dbr->tableNames('user','watchlist');
1544          * $sql = "SELECT wl_namespace,wl_title FROM $watchlist,$user
1545          *         WHERE wl_user=user_id AND wl_user=$nameWithQuotes";
1546          */
1547         public function tableNamesN() {
1548                 $inArray = func_get_args();
1549                 $retVal = array();
1550                 foreach ( $inArray as $name ) {
1551                         $retVal[] = $this->tableName( $name );
1552                 }
1553                 return $retVal;
1554         }
1555
1556         /**
1557          * @private
1558          */
1559         function tableNamesWithUseIndex( $tables, $use_index ) {
1560                 $ret = array();
1561
1562                 foreach ( $tables as $table )
1563                         if ( @$use_index[$table] !== null )
1564                                 $ret[] = $this->tableName( $table ) . ' ' . $this->useIndexClause( implode( ',', (array)$use_index[$table] ) );
1565                         else
1566                                 $ret[] = $this->tableName( $table );
1567
1568                 return implode( ',', $ret );
1569         }
1570
1571         /**
1572          * Wrapper for addslashes()
1573          * @param string $s String to be slashed.
1574          * @return string slashed string.
1575          */
1576         function strencode( $s ) {
1577                 return mysql_real_escape_string( $s, $this->mConn );
1578         }
1579
1580         /**
1581          * If it's a string, adds quotes and backslashes
1582          * Otherwise returns as-is
1583          */
1584         function addQuotes( $s ) {
1585                 if ( is_null( $s ) ) {
1586                         return 'NULL';
1587                 } else {
1588                         # This will also quote numeric values. This should be harmless,
1589                         # and protects against weird problems that occur when they really
1590                         # _are_ strings such as article titles and string->number->string
1591                         # conversion is not 1:1.
1592                         return "'" . $this->strencode( $s ) . "'";
1593                 }
1594         }
1595
1596         /**
1597          * Escape string for safe LIKE usage
1598          */
1599         function escapeLike( $s ) {
1600                 $s=$this->strencode( $s );
1601                 $s=str_replace(array('%','_'),array('\%','\_'),$s);
1602                 return $s;
1603         }
1604
1605         /**
1606          * Returns an appropriately quoted sequence value for inserting a new row.
1607          * MySQL has autoincrement fields, so this is just NULL. But the PostgreSQL
1608          * subclass will return an integer, and save the value for insertId()
1609          */
1610         function nextSequenceValue( $seqName ) {
1611                 return NULL;
1612         }
1613
1614         /**
1615          * USE INDEX clause
1616          * PostgreSQL doesn't have them and returns ""
1617          */
1618         function useIndexClause( $index ) {
1619                 return "FORCE INDEX ($index)";
1620         }
1621
1622         /**
1623          * REPLACE query wrapper
1624          * PostgreSQL simulates this with a DELETE followed by INSERT
1625          * $row is the row to insert, an associative array
1626          * $uniqueIndexes is an array of indexes. Each element may be either a
1627          * field name or an array of field names
1628          *
1629          * It may be more efficient to leave off unique indexes which are unlikely to collide.
1630          * However if you do this, you run the risk of encountering errors which wouldn't have
1631          * occurred in MySQL
1632          *
1633          * @todo migrate comment to phodocumentor format
1634          */
1635         function replace( $table, $uniqueIndexes, $rows, $fname = 'Database::replace' ) {
1636                 $table = $this->tableName( $table );
1637
1638                 # Single row case
1639                 if ( !is_array( reset( $rows ) ) ) {
1640                         $rows = array( $rows );
1641                 }
1642
1643                 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) .') VALUES ';
1644                 $first = true;
1645                 foreach ( $rows as $row ) {
1646                         if ( $first ) {
1647                                 $first = false;
1648                         } else {
1649                                 $sql .= ',';
1650                         }
1651                         $sql .= '(' . $this->makeList( $row ) . ')';
1652                 }
1653                 return $this->query( $sql, $fname );
1654         }
1655
1656         /**
1657          * DELETE where the condition is a join
1658          * MySQL does this with a multi-table DELETE syntax, PostgreSQL does it with sub-selects
1659          *
1660          * For safety, an empty $conds will not delete everything. If you want to delete all rows where the
1661          * join condition matches, set $conds='*'
1662          *
1663          * DO NOT put the join condition in $conds
1664          *
1665          * @param string $delTable The table to delete from.
1666          * @param string $joinTable The other table.
1667          * @param string $delVar The variable to join on, in the first table.
1668          * @param string $joinVar The variable to join on, in the second table.
1669          * @param array $conds Condition array of field names mapped to variables, ANDed together in the WHERE clause
1670          */
1671         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = 'Database::deleteJoin' ) {
1672                 if ( !$conds ) {
1673                         throw new DBUnexpectedError( $this, 'Database::deleteJoin() called with empty $conds' );
1674                 }
1675
1676                 $delTable = $this->tableName( $delTable );
1677                 $joinTable = $this->tableName( $joinTable );
1678                 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
1679                 if ( $conds != '*' ) {
1680                         $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
1681                 }
1682
1683                 return $this->query( $sql, $fname );
1684         }
1685
1686         /**
1687          * Returns the size of a text field, or -1 for "unlimited"
1688          */
1689         function textFieldSize( $table, $field ) {
1690                 $table = $this->tableName( $table );
1691                 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
1692                 $res = $this->query( $sql, 'Database::textFieldSize' );
1693                 $row = $this->fetchObject( $res );
1694                 $this->freeResult( $res );
1695
1696                 $m = array();
1697                 if ( preg_match( '/\((.*)\)/', $row->Type, $m ) ) {
1698                         $size = $m[1];
1699                 } else {
1700                         $size = -1;
1701                 }
1702                 return $size;
1703         }
1704
1705         /**
1706          * @return string Returns the text of the low priority option if it is supported, or a blank string otherwise
1707          */
1708         function lowPriorityOption() {
1709                 return 'LOW_PRIORITY';
1710         }
1711
1712         /**
1713          * DELETE query wrapper
1714          *
1715          * Use $conds == "*" to delete all rows
1716          */
1717         function delete( $table, $conds, $fname = 'Database::delete' ) {
1718                 if ( !$conds ) {
1719                         throw new DBUnexpectedError( $this, 'Database::delete() called with no conditions' );
1720                 }
1721                 $table = $this->tableName( $table );
1722                 $sql = "DELETE FROM $table";
1723                 if ( $conds != '*' ) {
1724                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
1725                 }
1726                 return $this->query( $sql, $fname );
1727         }
1728
1729         /**
1730          * INSERT SELECT wrapper
1731          * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
1732          * Source items may be literals rather than field names, but strings should be quoted with Database::addQuotes()
1733          * $conds may be "*" to copy the whole table
1734          * srcTable may be an array of tables.
1735          */
1736         function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = 'Database::insertSelect',
1737                 $insertOptions = array(), $selectOptions = array() )
1738         {
1739                 $destTable = $this->tableName( $destTable );
1740                 if ( is_array( $insertOptions ) ) {
1741                         $insertOptions = implode( ' ', $insertOptions );
1742                 }
1743                 if( !is_array( $selectOptions ) ) {
1744                         $selectOptions = array( $selectOptions );
1745                 }
1746                 list( $startOpts, $useIndex, $tailOpts ) = $this->makeSelectOptions( $selectOptions );
1747                 if( is_array( $srcTable ) ) {
1748                         $srcTable =  implode( ',', array_map( array( &$this, 'tableName' ), $srcTable ) );
1749                 } else {
1750                         $srcTable = $this->tableName( $srcTable );
1751                 }
1752                 $sql = "INSERT $insertOptions INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' .
1753                         " SELECT $startOpts " . implode( ',', $varMap ) .
1754                         " FROM $srcTable $useIndex ";
1755                 if ( $conds != '*' ) {
1756                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
1757                 }
1758                 $sql .= " $tailOpts";
1759                 return $this->query( $sql, $fname );
1760         }
1761
1762         /**
1763          * Construct a LIMIT query with optional offset
1764          * This is used for query pages
1765          * $sql string SQL query we will append the limit too
1766          * $limit integer the SQL limit
1767          * $offset integer the SQL offset (default false)
1768          */
1769         function limitResult($sql, $limit, $offset=false) {
1770                 if( !is_numeric($limit) ) {
1771                         throw new DBUnexpectedError( $this, "Invalid non-numeric limit passed to limitResult()\n" );
1772                 }
1773                 return " $sql LIMIT "
1774                                 . ( (is_numeric($offset) && $offset != 0) ? "{$offset}," : "" )
1775                                 . "{$limit} ";
1776         }
1777         function limitResultForUpdate($sql, $num) {
1778                 return $this->limitResult($sql, $num, 0);
1779         }
1780
1781         /**
1782          * Returns an SQL expression for a simple conditional.
1783          * Uses IF on MySQL.
1784          *
1785          * @param string $cond SQL expression which will result in a boolean value
1786          * @param string $trueVal SQL expression to return if true
1787          * @param string $falseVal SQL expression to return if false
1788          * @return string SQL fragment
1789          */
1790         function conditional( $cond, $trueVal, $falseVal ) {
1791                 return " IF($cond, $trueVal, $falseVal) ";
1792         }
1793
1794         /**
1795          * Determines if the last failure was due to a deadlock
1796          */
1797         function wasDeadlock() {
1798                 return $this->lastErrno() == 1213;
1799         }
1800
1801         /**
1802          * Perform a deadlock-prone transaction.
1803          *
1804          * This function invokes a callback function to perform a set of write
1805          * queries. If a deadlock occurs during the processing, the transaction
1806          * will be rolled back and the callback function will be called again.
1807          *
1808          * Usage:
1809          *   $dbw->deadlockLoop( callback, ... );
1810          *
1811          * Extra arguments are passed through to the specified callback function.
1812          *
1813          * Returns whatever the callback function returned on its successful,
1814          * iteration, or false on error, for example if the retry limit was
1815          * reached.
1816          */
1817         function deadlockLoop() {
1818                 $myFname = 'Database::deadlockLoop';
1819
1820                 $this->begin();
1821                 $args = func_get_args();
1822                 $function = array_shift( $args );
1823                 $oldIgnore = $this->ignoreErrors( true );
1824                 $tries = DEADLOCK_TRIES;
1825                 if ( is_array( $function ) ) {
1826                         $fname = $function[0];
1827                 } else {
1828                         $fname = $function;
1829                 }
1830                 do {
1831                         $retVal = call_user_func_array( $function, $args );
1832                         $error = $this->lastError();
1833                         $errno = $this->lastErrno();
1834                         $sql = $this->lastQuery();
1835
1836                         if ( $errno ) {
1837                                 if ( $this->wasDeadlock() ) {
1838                                         # Retry
1839                                         usleep( mt_rand( DEADLOCK_DELAY_MIN, DEADLOCK_DELAY_MAX ) );
1840                                 } else {
1841                                         $this->reportQueryError( $error, $errno, $sql, $fname );
1842                                 }
1843                         }
1844                 } while( $this->wasDeadlock() && --$tries > 0 );
1845                 $this->ignoreErrors( $oldIgnore );
1846                 if ( $tries <= 0 ) {
1847                         $this->query( 'ROLLBACK', $myFname );
1848                         $this->reportQueryError( $error, $errno, $sql, $fname );
1849                         return false;
1850                 } else {
1851                         $this->query( 'COMMIT', $myFname );
1852                         return $retVal;
1853                 }
1854         }
1855
1856         /**
1857          * Do a SELECT MASTER_POS_WAIT()
1858          *
1859          * @param string $file the binlog file
1860          * @param string $pos the binlog position
1861          * @param integer $timeout the maximum number of seconds to wait for synchronisation
1862          */
1863         function masterPosWait( $file, $pos, $timeout ) {
1864                 $fname = 'Database::masterPosWait';
1865                 wfProfileIn( $fname );
1866
1867
1868                 # Commit any open transactions
1869                 $this->immediateCommit();
1870
1871                 # Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
1872                 $encFile = $this->strencode( $file );
1873                 $sql = "SELECT MASTER_POS_WAIT('$encFile', $pos, $timeout)";
1874                 $res = $this->doQuery( $sql );
1875                 if ( $res && $row = $this->fetchRow( $res ) ) {
1876                         $this->freeResult( $res );
1877                         wfProfileOut( $fname );
1878                         return $row[0];
1879                 } else {
1880                         wfProfileOut( $fname );
1881                         return false;
1882                 }
1883         }
1884
1885         /**
1886          * Get the position of the master from SHOW SLAVE STATUS
1887          */
1888         function getSlavePos() {
1889                 $res = $this->query( 'SHOW SLAVE STATUS', 'Database::getSlavePos' );
1890                 $row = $this->fetchObject( $res );
1891                 if ( $row ) {
1892                         return array( $row->Master_Log_File, $row->Read_Master_Log_Pos );
1893                 } else {
1894                         return array( false, false );
1895                 }
1896         }
1897
1898         /**
1899          * Get the position of the master from SHOW MASTER STATUS
1900          */
1901         function getMasterPos() {
1902                 $res = $this->query( 'SHOW MASTER STATUS', 'Database::getMasterPos' );
1903                 $row = $this->fetchObject( $res );
1904                 if ( $row ) {
1905                         return array( $row->File, $row->Position );
1906                 } else {
1907                         return array( false, false );
1908                 }
1909         }
1910
1911         /**
1912          * Begin a transaction, committing any previously open transaction
1913          */
1914         function begin( $fname = 'Database::begin' ) {
1915                 $this->query( 'BEGIN', $fname );
1916                 $this->mTrxLevel = 1;
1917         }
1918
1919         /**
1920          * End a transaction
1921          */
1922         function commit( $fname = 'Database::commit' ) {
1923                 $this->query( 'COMMIT', $fname );
1924                 $this->mTrxLevel = 0;
1925         }
1926
1927         /**
1928          * Rollback a transaction
1929          */
1930         function rollback( $fname = 'Database::rollback' ) {
1931                 $this->query( 'ROLLBACK', $fname );
1932                 $this->mTrxLevel = 0;
1933         }
1934
1935         /**
1936          * Begin a transaction, committing any previously open transaction
1937          * @deprecated use begin()
1938          */
1939         function immediateBegin( $fname = 'Database::immediateBegin' ) {
1940                 $this->begin();
1941         }
1942
1943         /**
1944          * Commit transaction, if one is open
1945          * @deprecated use commit()
1946          */
1947         function immediateCommit( $fname = 'Database::immediateCommit' ) {
1948                 $this->commit();
1949         }
1950
1951         /**
1952          * Return MW-style timestamp used for MySQL schema
1953          */
1954         function timestamp( $ts=0 ) {
1955                 return wfTimestamp(TS_MW,$ts);
1956         }
1957
1958         /**
1959          * Local database timestamp format or null
1960          */
1961         function timestampOrNull( $ts = null ) {
1962                 if( is_null( $ts ) ) {
1963                         return null;
1964                 } else {
1965                         return $this->timestamp( $ts );
1966                 }
1967         }
1968
1969         /**
1970          * @todo document
1971          */
1972         function resultObject( $result ) {
1973                 if( empty( $result ) ) {
1974                         return NULL;
1975                 } else {
1976                         return new ResultWrapper( $this, $result );
1977                 }
1978         }
1979
1980         /**
1981          * Return aggregated value alias
1982          */
1983         function aggregateValue ($valuedata,$valuename='value') {
1984                 return $valuename;
1985         }
1986
1987         /**
1988          * @return string wikitext of a link to the server software's web site
1989          */
1990         function getSoftwareLink() {
1991                 return "[http://www.mysql.com/ MySQL]";
1992         }
1993
1994         /**
1995          * @return string Version information from the database
1996          */
1997         function getServerVersion() {
1998                 return mysql_get_server_info( $this->mConn );
1999         }
2000
2001         /**
2002          * Ping the server and try to reconnect if it there is no connection
2003          */
2004         function ping() {
2005                 if( function_exists( 'mysql_ping' ) ) {
2006                         return mysql_ping( $this->mConn );
2007                 } else {
2008                         wfDebug( "Tried to call mysql_ping but this is ancient PHP version. Faking it!\n" );
2009                         return true;
2010                 }
2011         }
2012
2013         /**
2014          * Get slave lag.
2015          * At the moment, this will only work if the DB user has the PROCESS privilege
2016          */
2017         function getLag() {
2018                 $res = $this->query( 'SHOW PROCESSLIST' );
2019                 # Find slave SQL thread. Assumed to be the second one running, which is a bit
2020                 # dubious, but unfortunately there's no easy rigorous way
2021                 while ( $row = $this->fetchObject( $res ) ) {
2022                         /* This should work for most situations - when default db
2023                          * for thread is not specified, it had no events executed,
2024                          * and therefore it doesn't know yet how lagged it is.
2025                          *
2026                          * Relay log I/O thread does not select databases.
2027                          */
2028                         if ( $row->User == 'system user' &&
2029                                 $row->State != 'Waiting for master to send event' &&
2030                                 $row->State != 'Connecting to master' &&
2031                                 $row->State != 'Queueing master event to the relay log' &&
2032                                 $row->State != 'Waiting for master update' &&
2033                                 $row->State != 'Requesting binlog dump'
2034                                 ) {
2035                                 # This is it, return the time (except -ve)
2036                                 if ( $row->Time > 0x7fffffff ) {
2037                                         return false;
2038                                 } else {
2039                                         return $row->Time;
2040                                 }
2041                         }
2042                 }
2043                 return false;
2044         }
2045
2046         /**
2047          * Get status information from SHOW STATUS in an associative array
2048          */
2049         function getStatus($which="%") {
2050                 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
2051                 $status = array();
2052                 while ( $row = $this->fetchObject( $res ) ) {
2053                         $status[$row->Variable_name] = $row->Value;
2054                 }
2055                 return $status;
2056         }
2057
2058         /**
2059          * Return the maximum number of items allowed in a list, or 0 for unlimited.
2060          */
2061         function maxListLen() {
2062                 return 0;
2063         }
2064
2065         function encodeBlob($b) {
2066                 return $b;
2067         }
2068
2069         function decodeBlob($b) {
2070                 return $b;
2071         }
2072
2073         /**
2074          * Override database's default connection timeout.
2075          * May be useful for very long batch queries such as
2076          * full-wiki dumps, where a single query reads out
2077          * over hours or days.
2078          * @param int $timeout in seconds
2079          */
2080         public function setTimeout( $timeout ) {
2081                 $this->query( "SET net_read_timeout=$timeout" );
2082                 $this->query( "SET net_write_timeout=$timeout" );
2083         }
2084
2085         /**
2086          * Read and execute SQL commands from a file.
2087          * Returns true on success, error string on failure
2088          */
2089         function sourceFile( $filename ) {
2090                 $fp = fopen( $filename, 'r' );
2091                 if ( false === $fp ) {
2092                         return "Could not open \"{$filename}\".\n";
2093                 }
2094
2095                 $cmd = "";
2096                 $done = false;
2097                 $dollarquote = false;
2098
2099                 while ( ! feof( $fp ) ) {
2100                         $line = trim( fgets( $fp, 1024 ) );
2101                         $sl = strlen( $line ) - 1;
2102
2103                         if ( $sl < 0 ) { continue; }
2104                         if ( '-' == $line{0} && '-' == $line{1} ) { continue; }
2105
2106                         ## Allow dollar quoting for function declarations
2107                         if (substr($line,0,4) == '$mw$') {
2108                                 if ($dollarquote) {
2109                                         $dollarquote = false;
2110                                         $done = true;
2111                                 }
2112                                 else {
2113                                         $dollarquote = true;
2114                                 }
2115                         }
2116                         else if (!$dollarquote) {
2117                                 if ( ';' == $line{$sl} && ($sl < 2 || ';' != $line{$sl - 1})) {
2118                                         $done = true;
2119                                         $line = substr( $line, 0, $sl );
2120                                 }
2121                         }
2122
2123                         if ( '' != $cmd ) { $cmd .= ' '; }
2124                         $cmd .= "$line\n";
2125
2126                         if ( $done ) {
2127                                 $cmd = str_replace(';;', ";", $cmd);
2128                                 $cmd = $this->replaceVars( $cmd );
2129                                 $res = $this->query( $cmd, 'dbsource', true );
2130
2131                                 if ( false === $res ) {
2132                                         $err = $this->lastError();
2133                                         return "Query \"{$cmd}\" failed with error code \"$err\".\n";
2134                                 }
2135
2136                                 $cmd = '';
2137                                 $done = false;
2138                         }
2139                 }
2140                 fclose( $fp );
2141                 return true;
2142         }
2143
2144         /**
2145          * Replace variables in sourced SQL
2146          */
2147         protected function replaceVars( $ins ) {
2148                 $varnames = array(
2149                         'wgDBserver', 'wgDBname', 'wgDBintlname', 'wgDBuser',
2150                         'wgDBpassword', 'wgDBsqluser', 'wgDBsqlpassword',
2151                         'wgDBadminuser', 'wgDBadminpassword',
2152                 );
2153
2154                 // Ordinary variables
2155                 foreach ( $varnames as $var ) {
2156                         if( isset( $GLOBALS[$var] ) ) {
2157                                 $val = addslashes( $GLOBALS[$var] ); // FIXME: safety check?
2158                                 $ins = str_replace( '{$' . $var . '}', $val, $ins );
2159                                 $ins = str_replace( '/*$' . $var . '*/`', '`' . $val, $ins );
2160                                 $ins = str_replace( '/*$' . $var . '*/', $val, $ins );
2161                         }
2162                 }
2163
2164                 // Table prefixes
2165                 $ins = preg_replace_callback( '/\/\*(?:\$wgDBprefix|_)\*\/([a-z_]*)/',
2166                         array( &$this, 'tableNameCallback' ), $ins );
2167                 return $ins;
2168         }
2169
2170         /**
2171          * Table name callback
2172          * @private
2173          */
2174         protected function tableNameCallback( $matches ) {
2175                 return $this->tableName( $matches[1] );
2176         }
2177
2178 }
2179
2180 /**
2181  * Database abstraction object for mySQL
2182  * Inherit all methods and properties of Database::Database()
2183  *
2184  * @see Database
2185  */
2186 class DatabaseMysql extends Database {
2187         # Inherit all
2188 }
2189
2190
2191 /**
2192  * Result wrapper for grabbing data queried by someone else
2193  *
2194  */
2195 class ResultWrapper {
2196         var $db, $result;
2197
2198         /**
2199          * @todo document
2200          */
2201         function ResultWrapper( &$database, $result ) {
2202                 $this->db =& $database;
2203                 $this->result =& $result;
2204         }
2205
2206         /**
2207          * @todo document
2208          */
2209         function numRows() {
2210                 return $this->db->numRows( $this->result );
2211         }
2212
2213         /**
2214          * @todo document
2215          */
2216         function fetchObject() {
2217                 return $this->db->fetchObject( $this->result );
2218         }
2219
2220         /**
2221          * @todo document
2222          */
2223         function fetchRow() {
2224                 return $this->db->fetchRow( $this->result );
2225         }
2226
2227         /**
2228          * @todo document
2229          */
2230         function free() {
2231                 $this->db->freeResult( $this->result );
2232                 unset( $this->result );
2233                 unset( $this->db );
2234         }
2235
2236         function seek( $row ) {
2237                 $this->db->dataSeek( $this->result, $row );
2238         }
2239
2240         function rewind() {
2241                 if ($this->numRows()) {
2242                         $this->db->dataSeek($this->result, 0);
2243                 }
2244         }
2245
2246 }
2247
2248 ?>