includes/db/DatabaseMysqlBase.php

   1 <?php
   2 /**
   3  * This is the MySQL database abstraction layer.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Database
  22  */
  23
  24 /**
  25  * Database abstraction object for MySQL.
  26  * Defines methods independent on used MySQL extension.
  27  *
  28  * @ingroup Database
  29  * @since 1.22
  30  * @see Database
  31  */
  32 abstract class DatabaseMysqlBase extends DatabaseBase {
  33         /** @var MysqlMasterPos */
  34         protected $lastKnownSlavePos;
  35
  36         /**
  37          * @return string
  38          */
  39         function getType() {
  40                 return 'mysql';
  41         }
  42
  43         /**
  44          * @param $server string
  45          * @param $user string
  46          * @param $password string
  47          * @param $dbName string
  48          * @return bool
  49          * @throws DBConnectionError
  50          */
  51         function open( $server, $user, $password, $dbName ) {
  52                 global $wgAllDBsAreLocalhost, $wgDBmysql5, $wgSQLMode;
  53                 wfProfileIn( __METHOD__ );
  54
  55                 # Debugging hack -- fake cluster
  56                 if ( $wgAllDBsAreLocalhost ) {
  57                         $realServer = 'localhost';
  58                 } else {
  59                         $realServer = $server;
  60                 }
  61                 $this->close();
  62                 $this->mServer = $server;
  63                 $this->mUser = $user;
  64                 $this->mPassword = $password;
  65                 $this->mDBname = $dbName;
  66
  67                 wfProfileIn( "dbconnect-$server" );
  68
  69                 # The kernel's default SYN retransmission period is far too slow for us,
  70                 # so we use a short timeout plus a manual retry. Retrying means that a small
  71                 # but finite rate of SYN packet loss won't cause user-visible errors.
  72                 $this->mConn = false;
  73                 $this->installErrorHandler();
  74                 try {
  75                         $this->mConn = $this->mysqlConnect( $realServer );
  76                 } catch ( Exception $ex ) {
  77                         wfProfileOut( "dbconnect-$server" );
  78                         wfProfileOut( __METHOD__ );
  79                         $this->restoreErrorHandler();
  80                         throw $ex;
  81                 }
  82                 $error = $this->restoreErrorHandler();
  83
  84                 wfProfileOut( "dbconnect-$server" );
  85
  86                 # Always log connection errors
  87                 if ( !$this->mConn ) {
  88                         if ( !$error ) {
  89                                 $error = $this->lastError();
  90                         }
  91                         wfLogDBError( "Error connecting to {$this->mServer}: $error\n" );
  92                         wfDebug( "DB connection error\n" .
  93                                 "Server: $server, User: $user, Password: " .
  94                                 substr( $password, 0, 3 ) . "..., error: " . $error . "\n" );
  95
  96                         wfProfileOut( __METHOD__ );
  97
  98                         return $this->reportConnectionError( $error );
  99                 }
 100
 101                 if ( $dbName != '' ) {
 102                         wfSuppressWarnings();
 103                         $success = $this->selectDB( $dbName );
 104                         wfRestoreWarnings();
 105                         if ( !$success ) {
 106                                 wfLogDBError( "Error selecting database $dbName on server {$this->mServer}\n" );
 107                                 wfDebug( "Error selecting database $dbName on server {$this->mServer} " .
 108                                         "from client host " . wfHostname() . "\n" );
 109
 110                                 wfProfileOut( __METHOD__ );
 111
 112                                 return $this->reportConnectionError( "Error selecting database $dbName" );
 113                         }
 114                 }
 115
 116                 // Tell the server we're communicating with it in UTF-8.
 117                 // This may engage various charset conversions.
 118                 if ( $wgDBmysql5 ) {
 119                         $this->mysqlSetCharset( 'utf8' );
 120                 } else {
 121                         $this->mysqlSetCharset( 'binary' );
 122                 }
 123                 // Set SQL mode, default is turning them all off, can be overridden or skipped with null
 124                 if ( is_string( $wgSQLMode ) ) {
 125                         $mode = $this->addQuotes( $wgSQLMode );
 126                         // Use doQuery() to avoid opening implicit transactions (DBO_TRX)
 127                         $success = $this->doQuery( "SET sql_mode = $mode", __METHOD__ );
 128                         if ( !$success ) {
 129                                 wfLogDBError( "Error setting sql_mode to $mode on server {$this->mServer}" );
 130                                 wfProfileOut( __METHOD__ );
 131                                 return $this->reportConnectionError( "Error setting sql_mode to $mode" );
 132                         }
 133                 }
 134
 135                 $this->mOpened = true;
 136                 wfProfileOut( __METHOD__ );
 137
 138                 return true;
 139         }
 140
 141         /**
 142          * Open a connection to a MySQL server
 143          *
 144          * @param $realServer string
 145          * @return mixed Raw connection
 146          * @throws DBConnectionError
 147          */
 148         abstract protected function mysqlConnect( $realServer );
 149
 150         /**
 151          * Set the character set of the MySQL link
 152          *
 153          * @param string $charset
 154          * @return bool
 155          */
 156         abstract protected function mysqlSetCharset( $charset );
 157
 158         /**
 159          * @param $res ResultWrapper
 160          * @throws DBUnexpectedError
 161          */
 162         function freeResult( $res ) {
 163                 if ( $res instanceof ResultWrapper ) {
 164                         $res = $res->result;
 165                 }
 166                 wfSuppressWarnings();
 167                 $ok = $this->mysqlFreeResult( $res );
 168                 wfRestoreWarnings();
 169                 if ( !$ok ) {
 170                         throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
 171                 }
 172         }
 173
 174         /**
 175          * Free result memory
 176          *
 177          * @param $res Raw result
 178          * @return bool
 179          */
 180         abstract protected function mysqlFreeResult( $res );
 181
 182         /**
 183          * @param $res ResultWrapper
 184          * @return object|bool
 185          * @throws DBUnexpectedError
 186          */
 187         function fetchObject( $res ) {
 188                 if ( $res instanceof ResultWrapper ) {
 189                         $res = $res->result;
 190                 }
 191                 wfSuppressWarnings();
 192                 $row = $this->mysqlFetchObject( $res );
 193                 wfRestoreWarnings();
 194
 195                 $errno = $this->lastErrno();
 196                 // Unfortunately, mysql_fetch_object does not reset the last errno.
 197                 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
 198                 // these are the only errors mysql_fetch_object can cause.
 199                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 200                 if ( $errno == 2000 || $errno == 2013 ) {
 201                         throw new DBUnexpectedError(
 202                                 $this,
 203                                 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() )
 204                         );
 205                 }
 206
 207                 return $row;
 208         }
 209
 210         /**
 211          * Fetch a result row as an object
 212          *
 213          * @param $res Raw result
 214          * @return stdClass
 215          */
 216         abstract protected function mysqlFetchObject( $res );
 217
 218         /**
 219          * @param $res ResultWrapper
 220          * @return array|bool
 221          * @throws DBUnexpectedError
 222          */
 223         function fetchRow( $res ) {
 224                 if ( $res instanceof ResultWrapper ) {
 225                         $res = $res->result;
 226                 }
 227                 wfSuppressWarnings();
 228                 $row = $this->mysqlFetchArray( $res );
 229                 wfRestoreWarnings();
 230
 231                 $errno = $this->lastErrno();
 232                 // Unfortunately, mysql_fetch_array does not reset the last errno.
 233                 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
 234                 // these are the only errors mysql_fetch_array can cause.
 235                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 236                 if ( $errno == 2000 || $errno == 2013 ) {
 237                         throw new DBUnexpectedError(
 238                                 $this,
 239                                 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() )
 240                         );
 241                 }
 242
 243                 return $row;
 244         }
 245
 246         /**
 247          * Fetch a result row as an associative and numeric array
 248          *
 249          * @param $res Raw result
 250          * @return array
 251          */
 252         abstract protected function mysqlFetchArray( $res );
 253
 254         /**
 255          * @throws DBUnexpectedError
 256          * @param $res ResultWrapper
 257          * @return int
 258          */
 259         function numRows( $res ) {
 260                 if ( $res instanceof ResultWrapper ) {
 261                         $res = $res->result;
 262                 }
 263                 wfSuppressWarnings();
 264                 $n = $this->mysqlNumRows( $res );
 265                 wfRestoreWarnings();
 266
 267                 // Unfortunately, mysql_num_rows does not reset the last errno.
 268                 // We are not checking for any errors here, since
 269                 // these are no errors mysql_num_rows can cause.
 270                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 271                 // See https://bugzilla.wikimedia.org/42430
 272                 return $n;
 273         }
 274
 275         /**
 276          * Get number of rows in result
 277          *
 278          * @param $res Raw result
 279          * @return int
 280          */
 281         abstract protected function mysqlNumRows( $res );
 282
 283         /**
 284          * @param $res ResultWrapper
 285          * @return int
 286          */
 287         function numFields( $res ) {
 288                 if ( $res instanceof ResultWrapper ) {
 289                         $res = $res->result;
 290                 }
 291
 292                 return $this->mysqlNumFields( $res );
 293         }
 294
 295         /**
 296          * Get number of fields in result
 297          *
 298          * @param $res Raw result
 299          * @return int
 300          */
 301         abstract protected function mysqlNumFields( $res );
 302
 303         /**
 304          * @param $res ResultWrapper
 305          * @param $n string
 306          * @return string
 307          */
 308         function fieldName( $res, $n ) {
 309                 if ( $res instanceof ResultWrapper ) {
 310                         $res = $res->result;
 311                 }
 312
 313                 return $this->mysqlFieldName( $res, $n );
 314         }
 315
 316         /**
 317          * Get the name of the specified field in a result
 318          *
 319          * @param $res Raw result
 320          * @param $n int
 321          * @return string
 322          */
 323         abstract protected function mysqlFieldName( $res, $n );
 324
 325         /**
 326          * @param $res ResultWrapper
 327          * @param $row
 328          * @return bool
 329          */
 330         function dataSeek( $res, $row ) {
 331                 if ( $res instanceof ResultWrapper ) {
 332                         $res = $res->result;
 333                 }
 334
 335                 return $this->mysqlDataSeek( $res, $row );
 336         }
 337
 338         /**
 339          * Move internal result pointer
 340          *
 341          * @param $res Raw result
 342          * @param $row int
 343          * @return bool
 344          */
 345         abstract protected function mysqlDataSeek( $res, $row );
 346
 347         /**
 348          * @return string
 349          */
 350         function lastError() {
 351                 if ( $this->mConn ) {
 352                         # Even if it's non-zero, it can still be invalid
 353                         wfSuppressWarnings();
 354                         $error = $this->mysqlError( $this->mConn );
 355                         if ( !$error ) {
 356                                 $error = $this->mysqlError();
 357                         }
 358                         wfRestoreWarnings();
 359                 } else {
 360                         $error = $this->mysqlError();
 361                 }
 362                 if ( $error ) {
 363                         $error .= ' (' . $this->mServer . ')';
 364                 }
 365
 366                 return $error;
 367         }
 368
 369         /**
 370          * Returns the text of the error message from previous MySQL operation
 371          *
 372          * @param $conn Raw connection
 373          * @return string
 374          */
 375         abstract protected function mysqlError( $conn = null );
 376
 377         /**
 378          * @param $table string
 379          * @param $uniqueIndexes
 380          * @param $rows array
 381          * @param $fname string
 382          * @return ResultWrapper
 383          */
 384         function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
 385                 return $this->nativeReplace( $table, $rows, $fname );
 386         }
 387
 388         /**
 389          * Estimate rows in dataset
 390          * Returns estimated count, based on EXPLAIN output
 391          * Takes same arguments as Database::select()
 392          *
 393          * @param $table string|array
 394          * @param $vars string|array
 395          * @param $conds string|array
 396          * @param $fname string
 397          * @param $options string|array
 398          * @return int
 399          */
 400         public function estimateRowCount( $table, $vars = '*', $conds = '',
 401                 $fname = __METHOD__, $options = array()
 402         ) {
 403                 $options['EXPLAIN'] = true;
 404                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 405                 if ( $res === false ) {
 406                         return false;
 407                 }
 408                 if ( !$this->numRows( $res ) ) {
 409                         return 0;
 410                 }
 411
 412                 $rows = 1;
 413                 foreach ( $res as $plan ) {
 414                         $rows *= $plan->rows > 0 ? $plan->rows : 1; // avoid resetting to zero
 415                 }
 416
 417                 return $rows;
 418         }
 419
 420         /**
 421          * @param $table string
 422          * @param $field string
 423          * @return bool|MySQLField
 424          */
 425         function fieldInfo( $table, $field ) {
 426                 $table = $this->tableName( $table );
 427                 $res = $this->query( "SELECT * FROM $table LIMIT 1", __METHOD__, true );
 428                 if ( !$res ) {
 429                         return false;
 430                 }
 431                 $n = $this->mysqlNumFields( $res->result );
 432                 for ( $i = 0; $i < $n; $i++ ) {
 433                         $meta = $this->mysqlFetchField( $res->result, $i );
 434                         if ( $field == $meta->name ) {
 435                                 return new MySQLField( $meta );
 436                         }
 437                 }
 438
 439                 return false;
 440         }
 441
 442         /**
 443          * Get column information from a result
 444          *
 445          * @param $res Raw result
 446          * @param $n int
 447          * @return stdClass
 448          */
 449         abstract protected function mysqlFetchField( $res, $n );
 450
 451         /**
 452          * Get information about an index into an object
 453          * Returns false if the index does not exist
 454          *
 455          * @param $table string
 456          * @param $index string
 457          * @param $fname string
 458          * @return bool|array|null False or null on failure
 459          */
 460         function indexInfo( $table, $index, $fname = __METHOD__ ) {
 461                 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
 462                 # SHOW INDEX should work for 3.x and up:
 463                 # http://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
 464                 $table = $this->tableName( $table );
 465                 $index = $this->indexName( $index );
 466
 467                 $sql = 'SHOW INDEX FROM ' . $table;
 468                 $res = $this->query( $sql, $fname );
 469
 470                 if ( !$res ) {
 471                         return null;
 472                 }
 473
 474                 $result = array();
 475
 476                 foreach ( $res as $row ) {
 477                         if ( $row->Key_name == $index ) {
 478                                 $result[] = $row;
 479                         }
 480                 }
 481
 482                 return empty( $result ) ? false : $result;
 483         }
 484
 485         /**
 486          * @param $s string
 487          *
 488          * @return string
 489          */
 490         function strencode( $s ) {
 491                 $sQuoted = $this->mysqlRealEscapeString( $s );
 492
 493                 if ( $sQuoted === false ) {
 494                         $this->ping();
 495                         $sQuoted = $this->mysqlRealEscapeString( $s );
 496                 }
 497
 498                 return $sQuoted;
 499         }
 500
 501         /**
 502          * MySQL uses `backticks` for identifier quoting instead of the sql standard "double quotes".
 503          *
 504          * @param $s string
 505          *
 506          * @return string
 507          */
 508         public function addIdentifierQuotes( $s ) {
 509                 // Characters in the range \u0001-\uFFFF are valid in a quoted identifier
 510                 // Remove NUL bytes and escape backticks by doubling
 511                 return '`' . str_replace( array( "\0", '`' ), array( '', '``' ), $s ) . '`';
 512         }
 513
 514         /**
 515          * @param $name string
 516          * @return bool
 517          */
 518         public function isQuotedIdentifier( $name ) {
 519                 return strlen( $name ) && $name[0] == '`' && substr( $name, -1, 1 ) == '`';
 520         }
 521
 522         /**
 523          * @return bool
 524          */
 525         function ping() {
 526                 $ping = $this->mysqlPing();
 527                 if ( $ping ) {
 528                         return true;
 529                 }
 530
 531                 $this->closeConnection();
 532                 $this->mOpened = false;
 533                 $this->mConn = false;
 534                 $this->open( $this->mServer, $this->mUser, $this->mPassword, $this->mDBname );
 535
 536                 return true;
 537         }
 538
 539         /**
 540          * Ping a server connection or reconnect if there is no connection
 541          *
 542          * @return bool
 543          */
 544         abstract protected function mysqlPing();
 545
 546         /**
 547          * Returns slave lag.
 548          *
 549          * This will do a SHOW SLAVE STATUS
 550          *
 551          * @return int
 552          */
 553         function getLag() {
 554                 if ( !is_null( $this->mFakeSlaveLag ) ) {
 555                         wfDebug( "getLag: fake slave lagged {$this->mFakeSlaveLag} seconds\n" );
 556
 557                         return $this->mFakeSlaveLag;
 558                 }
 559
 560                 return $this->getLagFromSlaveStatus();
 561         }
 562
 563         /**
 564          * @return bool|int
 565          */
 566         function getLagFromSlaveStatus() {
 567                 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__ );
 568                 if ( !$res ) {
 569                         return false;
 570                 }
 571                 $row = $res->fetchObject();
 572                 if ( !$row ) {
 573                         return false;
 574                 }
 575                 if ( strval( $row->Seconds_Behind_Master ) === '' ) {
 576                         return false;
 577                 } else {
 578                         return intval( $row->Seconds_Behind_Master );
 579                 }
 580         }
 581
 582         /**
 583          * @deprecated in 1.19, use getLagFromSlaveStatus
 584          *
 585          * @return bool|int
 586          */
 587         function getLagFromProcesslist() {
 588                 wfDeprecated( __METHOD__, '1.19' );
 589                 $res = $this->query( 'SHOW PROCESSLIST', __METHOD__ );
 590                 if ( !$res ) {
 591                         return false;
 592                 }
 593                 # Find slave SQL thread
 594                 foreach ( $res as $row ) {
 595                         /* This should work for most situations - when default db
 596                          * for thread is not specified, it had no events executed,
 597                          * and therefore it doesn't know yet how lagged it is.
 598                          *
 599                          * Relay log I/O thread does not select databases.
 600                          */
 601                         if ( $row->User == 'system user' &&
 602                                 $row->State != 'Waiting for master to send event' &&
 603                                 $row->State != 'Connecting to master' &&
 604                                 $row->State != 'Queueing master event to the relay log' &&
 605                                 $row->State != 'Waiting for master update' &&
 606                                 $row->State != 'Requesting binlog dump' &&
 607                                 $row->State != 'Waiting to reconnect after a failed master event read' &&
 608                                 $row->State != 'Reconnecting after a failed master event read' &&
 609                                 $row->State != 'Registering slave on master'
 610                         ) {
 611                                 # This is it, return the time (except -ve)
 612                                 if ( $row->Time > 0x7fffffff ) {
 613                                         return false;
 614                                 } else {
 615                                         return $row->Time;
 616                                 }
 617                         }
 618                 }
 619
 620                 return false;
 621         }
 622
 623         /**
 624          * Wait for the slave to catch up to a given master position.
 625          * @TODO: return values for this and base class are rubbish
 626          *
 627          * @param $pos DBMasterPos object
 628          * @param $timeout Integer: the maximum number of seconds to wait for synchronisation
 629          * @return bool|string
 630          */
 631         function masterPosWait( DBMasterPos $pos, $timeout ) {
 632                 if ( $this->lastKnownSlavePos && $this->lastKnownSlavePos->hasReached( $pos ) ) {
 633                         return '0'; // http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html
 634                 }
 635
 636                 wfProfileIn( __METHOD__ );
 637                 # Commit any open transactions
 638                 $this->commit( __METHOD__, 'flush' );
 639
 640                 if ( !is_null( $this->mFakeSlaveLag ) ) {
 641                         $status = parent::masterPosWait( $pos, $timeout );
 642                         wfProfileOut( __METHOD__ );
 643
 644                         return $status;
 645                 }
 646
 647                 # Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
 648                 $encFile = $this->addQuotes( $pos->file );
 649                 $encPos = intval( $pos->pos );
 650                 $sql = "SELECT MASTER_POS_WAIT($encFile, $encPos, $timeout)";
 651                 $res = $this->doQuery( $sql );
 652
 653                 $status = false;
 654                 if ( $res && $row = $this->fetchRow( $res ) ) {
 655                         $status = $row[0]; // can be NULL, -1, or 0+ per the MySQL manual
 656                         if ( ctype_digit( $status ) ) { // success
 657                                 $this->lastKnownSlavePos = $pos;
 658                         }
 659                 }
 660
 661                 wfProfileOut( __METHOD__ );
 662
 663                 return $status;
 664         }
 665
 666         /**
 667          * Get the position of the master from SHOW SLAVE STATUS
 668          *
 669          * @return MySQLMasterPos|bool
 670          */
 671         function getSlavePos() {
 672                 if ( !is_null( $this->mFakeSlaveLag ) ) {
 673                         return parent::getSlavePos();
 674                 }
 675
 676                 $res = $this->query( 'SHOW SLAVE STATUS', 'DatabaseBase::getSlavePos' );
 677                 $row = $this->fetchObject( $res );
 678
 679                 if ( $row ) {
 680                         $pos = isset( $row->Exec_master_log_pos )
 681                                 ? $row->Exec_master_log_pos
 682                                 : $row->Exec_Master_Log_Pos;
 683
 684                         return new MySQLMasterPos( $row->Relay_Master_Log_File, $pos );
 685                 } else {
 686                         return false;
 687                 }
 688         }
 689
 690         /**
 691          * Get the position of the master from SHOW MASTER STATUS
 692          *
 693          * @return MySQLMasterPos|bool
 694          */
 695         function getMasterPos() {
 696                 if ( $this->mFakeMaster ) {
 697                         return parent::getMasterPos();
 698                 }
 699
 700                 $res = $this->query( 'SHOW MASTER STATUS', 'DatabaseBase::getMasterPos' );
 701                 $row = $this->fetchObject( $res );
 702
 703                 if ( $row ) {
 704                         return new MySQLMasterPos( $row->File, $row->Position );
 705                 } else {
 706                         return false;
 707                 }
 708         }
 709
 710         /**
 711          * @param $index
 712          * @return string
 713          */
 714         function useIndexClause( $index ) {
 715                 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
 716         }
 717
 718         /**
 719          * @return string
 720          */
 721         function lowPriorityOption() {
 722                 return 'LOW_PRIORITY';
 723         }
 724
 725         /**
 726          * @return string
 727          */
 728         public function getSoftwareLink() {
 729                 return '[http://www.mysql.com/ MySQL]';
 730         }
 731
 732         /**
 733          * @param $options array
 734          */
 735         public function setSessionOptions( array $options ) {
 736                 if ( isset( $options['connTimeout'] ) ) {
 737                         $timeout = (int)$options['connTimeout'];
 738                         $this->query( "SET net_read_timeout=$timeout" );
 739                         $this->query( "SET net_write_timeout=$timeout" );
 740                 }
 741         }
 742
 743         public function streamStatementEnd( &$sql, &$newLine ) {
 744                 if ( strtoupper( substr( $newLine, 0, 9 ) ) == 'DELIMITER' ) {
 745                         preg_match( '/^DELIMITER\s+(\S+)/', $newLine, $m );
 746                         $this->delimiter = $m[1];
 747                         $newLine = '';
 748                 }
 749
 750                 return parent::streamStatementEnd( $sql, $newLine );
 751         }
 752
 753         /**
 754          * Check to see if a named lock is available. This is non-blocking.
 755          *
 756          * @param string $lockName name of lock to poll
 757          * @param string $method name of method calling us
 758          * @return Boolean
 759          * @since 1.20
 760          */
 761         public function lockIsFree( $lockName, $method ) {
 762                 $lockName = $this->addQuotes( $lockName );
 763                 $result = $this->query( "SELECT IS_FREE_LOCK($lockName) AS lockstatus", $method );
 764                 $row = $this->fetchObject( $result );
 765
 766                 return ( $row->lockstatus == 1 );
 767         }
 768
 769         /**
 770          * @param $lockName string
 771          * @param $method string
 772          * @param $timeout int
 773          * @return bool
 774          */
 775         public function lock( $lockName, $method, $timeout = 5 ) {
 776                 $lockName = $this->addQuotes( $lockName );
 777                 $result = $this->query( "SELECT GET_LOCK($lockName, $timeout) AS lockstatus", $method );
 778                 $row = $this->fetchObject( $result );
 779
 780                 if ( $row->lockstatus == 1 ) {
 781                         return true;
 782                 } else {
 783                         wfDebug( __METHOD__ . " failed to acquire lock\n" );
 784
 785                         return false;
 786                 }
 787         }
 788
 789         /**
 790          * FROM MYSQL DOCS:
 791          * http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
 792          * @param $lockName string
 793          * @param $method string
 794          * @return bool
 795          */
 796         public function unlock( $lockName, $method ) {
 797                 $lockName = $this->addQuotes( $lockName );
 798                 $result = $this->query( "SELECT RELEASE_LOCK($lockName) as lockstatus", $method );
 799                 $row = $this->fetchObject( $result );
 800
 801                 return ( $row->lockstatus == 1 );
 802         }
 803
 804         /**
 805          * @param $read array
 806          * @param $write array
 807          * @param $method string
 808          * @param $lowPriority bool
 809          * @return bool
 810          */
 811         public function lockTables( $read, $write, $method, $lowPriority = true ) {
 812                 $items = array();
 813
 814                 foreach ( $write as $table ) {
 815                         $tbl = $this->tableName( $table ) .
 816                                 ( $lowPriority ? ' LOW_PRIORITY' : '' ) .
 817                                 ' WRITE';
 818                         $items[] = $tbl;
 819                 }
 820                 foreach ( $read as $table ) {
 821                         $items[] = $this->tableName( $table ) . ' READ';
 822                 }
 823                 $sql = "LOCK TABLES " . implode( ',', $items );
 824                 $this->query( $sql, $method );
 825
 826                 return true;
 827         }
 828
 829         /**
 830          * @param $method string
 831          * @return bool
 832          */
 833         public function unlockTables( $method ) {
 834                 $this->query( "UNLOCK TABLES", $method );
 835
 836                 return true;
 837         }
 838
 839         /**
 840          * Get search engine class. All subclasses of this
 841          * need to implement this if they wish to use searching.
 842          *
 843          * @return String
 844          */
 845         public function getSearchEngine() {
 846                 return 'SearchMySQL';
 847         }
 848
 849         /**
 850          * @param bool $value
 851          * @return mixed
 852          */
 853         public function setBigSelects( $value = true ) {
 854                 if ( $value === 'default' ) {
 855                         if ( $this->mDefaultBigSelects === null ) {
 856                                 # Function hasn't been called before so it must already be set to the default
 857                                 return;
 858                         } else {
 859                                 $value = $this->mDefaultBigSelects;
 860                         }
 861                 } elseif ( $this->mDefaultBigSelects === null ) {
 862                         $this->mDefaultBigSelects = (bool)$this->selectField( false, '@@sql_big_selects' );
 863                 }
 864                 $encValue = $value ? '1' : '0';
 865                 $this->query( "SET sql_big_selects=$encValue", __METHOD__ );
 866         }
 867
 868         /**
 869          * DELETE where the condition is a join. MySql uses multi-table deletes.
 870          * @param $delTable string
 871          * @param $joinTable string
 872          * @param $delVar string
 873          * @param $joinVar string
 874          * @param $conds array|string
 875          * @param bool|string $fname bool
 876          * @throws DBUnexpectedError
 877          * @return bool|ResultWrapper
 878          */
 879         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = __METHOD__ ) {
 880                 if ( !$conds ) {
 881                         throw new DBUnexpectedError( $this, 'DatabaseBase::deleteJoin() called with empty $conds' );
 882                 }
 883
 884                 $delTable = $this->tableName( $delTable );
 885                 $joinTable = $this->tableName( $joinTable );
 886                 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
 887
 888                 if ( $conds != '*' ) {
 889                         $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
 890                 }
 891
 892                 return $this->query( $sql, $fname );
 893         }
 894
 895         /**
 896          * @param string $table
 897          * @param array $rows
 898          * @param array $uniqueIndexes
 899          * @param array $set
 900          * @param string $fname
 901          * @param array $options
 902          * @return bool
 903          */
 904         public function upsert(
 905                 $table, array $rows, array $uniqueIndexes, array $set, $fname = __METHOD__
 906         ) {
 907                 if ( !count( $rows ) ) {
 908                         return true; // nothing to do
 909                 }
 910                 $rows = is_array( reset( $rows ) ) ? $rows : array( $rows );
 911
 912                 $table = $this->tableName( $table );
 913                 $columns = array_keys( $rows[0] );
 914
 915                 $sql = "INSERT INTO $table (" . implode( ',', $columns ) . ') VALUES ';
 916                 $rowTuples = array();
 917                 foreach ( $rows as $row ) {
 918                         $rowTuples[] = '(' . $this->makeList( $row ) . ')';
 919                 }
 920                 $sql .= implode( ',', $rowTuples );
 921                 $sql .= " ON DUPLICATE KEY UPDATE " . $this->makeList( $set, LIST_SET );
 922
 923                 return (bool)$this->query( $sql, $fname );
 924         }
 925
 926         /**
 927          * Determines how long the server has been up
 928          *
 929          * @return int
 930          */
 931         function getServerUptime() {
 932                 $vars = $this->getMysqlStatus( 'Uptime' );
 933
 934                 return (int)$vars['Uptime'];
 935         }
 936
 937         /**
 938          * Determines if the last failure was due to a deadlock
 939          *
 940          * @return bool
 941          */
 942         function wasDeadlock() {
 943                 return $this->lastErrno() == 1213;
 944         }
 945
 946         /**
 947          * Determines if the last failure was due to a lock timeout
 948          *
 949          * @return bool
 950          */
 951         function wasLockTimeout() {
 952                 return $this->lastErrno() == 1205;
 953         }
 954
 955         /**
 956          * Determines if the last query error was something that should be dealt
 957          * with by pinging the connection and reissuing the query
 958          *
 959          * @return bool
 960          */
 961         function wasErrorReissuable() {
 962                 return $this->lastErrno() == 2013 || $this->lastErrno() == 2006;
 963         }
 964
 965         /**
 966          * Determines if the last failure was due to the database being read-only.
 967          *
 968          * @return bool
 969          */
 970         function wasReadOnlyError() {
 971                 return $this->lastErrno() == 1223 ||
 972                         ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
 973         }
 974
 975         /**
 976          * @param $oldName
 977          * @param $newName
 978          * @param $temporary bool
 979          * @param $fname string
 980          */
 981         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
 982                 $tmp = $temporary ? 'TEMPORARY ' : '';
 983                 $newName = $this->addIdentifierQuotes( $newName );
 984                 $oldName = $this->addIdentifierQuotes( $oldName );
 985                 $query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
 986                 $this->query( $query, $fname );
 987         }
 988
 989         /**
 990          * List all tables on the database
 991          *
 992          * @param string $prefix Only show tables with this prefix, e.g. mw_
 993          * @param string $fname calling function name
 994          * @return array
 995          */
 996         function listTables( $prefix = null, $fname = __METHOD__ ) {
 997                 $result = $this->query( "SHOW TABLES", $fname );
 998
 999                 $endArray = array();
1000
1001                 foreach ( $result as $table ) {
1002                         $vars = get_object_vars( $table );
1003                         $table = array_pop( $vars );
1004
1005                         if ( !$prefix || strpos( $table, $prefix ) === 0 ) {
1006                                 $endArray[] = $table;
1007                         }
1008                 }
1009
1010                 return $endArray;
1011         }
1012
1013         /**
1014          * @param $tableName
1015          * @param $fName string
1016          * @return bool|ResultWrapper
1017          */
1018         public function dropTable( $tableName, $fName = __METHOD__ ) {
1019                 if ( !$this->tableExists( $tableName, $fName ) ) {
1020                         return false;
1021                 }
1022
1023                 return $this->query( "DROP TABLE IF EXISTS " . $this->tableName( $tableName ), $fName );
1024         }
1025
1026         /**
1027          * @return array
1028          */
1029         protected function getDefaultSchemaVars() {
1030                 $vars = parent::getDefaultSchemaVars();
1031                 $vars['wgDBTableOptions'] = str_replace( 'TYPE', 'ENGINE', $GLOBALS['wgDBTableOptions'] );
1032                 $vars['wgDBTableOptions'] = str_replace(
1033                         'CHARSET=mysql4',
1034                         'CHARSET=binary',
1035                         $vars['wgDBTableOptions']
1036                 );
1037
1038                 return $vars;
1039         }
1040
1041         /**
1042          * Get status information from SHOW STATUS in an associative array
1043          *
1044          * @param $which string
1045          * @return array
1046          */
1047         function getMysqlStatus( $which = "%" ) {
1048                 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
1049                 $status = array();
1050
1051                 foreach ( $res as $row ) {
1052                         $status[$row->Variable_name] = $row->Value;
1053                 }
1054
1055                 return $status;
1056         }
1057
1058         /**
1059          * Lists VIEWs in the database
1060          *
1061          * @param string $prefix Only show VIEWs with this prefix, eg.
1062          * unit_test_, or $wgDBprefix. Default: null, would return all views.
1063          * @param string $fname Name of calling function
1064          * @return array
1065          * @since 1.22
1066          */
1067         public function listViews( $prefix = null, $fname = __METHOD__ ) {
1068
1069                 if ( !isset( $this->allViews ) ) {
1070
1071                         // The name of the column containing the name of the VIEW
1072                         $propertyName = 'Tables_in_' . $this->mDBname;
1073
1074                         // Query for the VIEWS
1075                         $result = $this->query( 'SHOW FULL TABLES WHERE TABLE_TYPE = "VIEW"' );
1076                         $this->allViews = array();
1077                         while ( ( $row = $this->fetchRow( $result ) ) !== false ) {
1078                                 array_push( $this->allViews, $row[$propertyName] );
1079                         }
1080                 }
1081
1082                 if ( is_null( $prefix ) || $prefix === '' ) {
1083                         return $this->allViews;
1084                 }
1085
1086                 $filteredViews = array();
1087                 foreach ( $this->allViews as $viewName ) {
1088                         // Does the name of this VIEW start with the table-prefix?
1089                         if ( strpos( $viewName, $prefix ) === 0 ) {
1090                                 array_push( $filteredViews, $viewName );
1091                         }
1092                 }
1093
1094                 return $filteredViews;
1095         }
1096
1097         /**
1098          * Differentiates between a TABLE and a VIEW.
1099          *
1100          * @param $name string: Name of the TABLE/VIEW to test
1101          * @return bool
1102          * @since 1.22
1103          */
1104         public function isView( $name, $prefix = null ) {
1105                 return in_array( $name, $this->listViews( $prefix ) );
1106         }
1107 }
1108
1109 /**
1110  * Utility class.
1111  * @ingroup Database
1112  */
1113 class MySQLField implements Field {
1114         private $name, $tablename, $default, $max_length, $nullable,
1115                 $is_pk, $is_unique, $is_multiple, $is_key, $type, $binary;
1116
1117         function __construct( $info ) {
1118                 $this->name = $info->name;
1119                 $this->tablename = $info->table;
1120                 $this->default = $info->def;
1121                 $this->max_length = $info->max_length;
1122                 $this->nullable = !$info->not_null;
1123                 $this->is_pk = $info->primary_key;
1124                 $this->is_unique = $info->unique_key;
1125                 $this->is_multiple = $info->multiple_key;
1126                 $this->is_key = ( $this->is_pk || $this->is_unique || $this->is_multiple );
1127                 $this->type = $info->type;
1128                 $this->binary = isset( $info->binary ) ? $info->binary : false;
1129         }
1130
1131         /**
1132          * @return string
1133          */
1134         function name() {
1135                 return $this->name;
1136         }
1137
1138         /**
1139          * @return string
1140          */
1141         function tableName() {
1142                 return $this->tableName;
1143         }
1144
1145         /**
1146          * @return string
1147          */
1148         function type() {
1149                 return $this->type;
1150         }
1151
1152         /**
1153          * @return bool
1154          */
1155         function isNullable() {
1156                 return $this->nullable;
1157         }
1158
1159         function defaultValue() {
1160                 return $this->default;
1161         }
1162
1163         /**
1164          * @return bool
1165          */
1166         function isKey() {
1167                 return $this->is_key;
1168         }
1169
1170         /**
1171          * @return bool
1172          */
1173         function isMultipleKey() {
1174                 return $this->is_multiple;
1175         }
1176
1177         function isBinary() {
1178                 return $this->binary;
1179         }
1180 }
1181
1182 class MySQLMasterPos implements DBMasterPos {
1183         var $file, $pos;
1184
1185         function __construct( $file, $pos ) {
1186                 $this->file = $file;
1187                 $this->pos = $pos;
1188         }
1189
1190         function __toString() {
1191                 // e.g db1034-bin.000976/843431247
1192                 return "{$this->file}/{$this->pos}";
1193         }
1194
1195         /**
1196          * @return array|false (int, int)
1197          */
1198         protected function getCoordinates() {
1199                 $m = array();
1200                 if ( preg_match( '!\.(\d+)/(\d+)$!', (string)$this, $m ) ) {
1201                         return array( (int)$m[1], (int)$m[2] );
1202                 }
1203
1204                 return false;
1205         }
1206
1207         function hasReached( MySQLMasterPos $pos ) {
1208                 $thisPos = $this->getCoordinates();
1209                 $thatPos = $pos->getCoordinates();
1210
1211                 return ( $thisPos && $thatPos && $thisPos >= $thatPos );
1212         }
1213 }