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