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         /** @var string|null */
  37         private $serverVersion = null;
  38
  39         /**
  40          * @return string
  41          */
  42         function getType() {
  43                 return 'mysql';
  44         }
  45
  46         /**
  47          * @param string $server
  48          * @param string $user
  49          * @param string $password
  50          * @param string $dbName
  51          * @throws Exception|DBConnectionError
  52          * @return bool
  53          */
  54         function open( $server, $user, $password, $dbName ) {
  55                 global $wgAllDBsAreLocalhost, $wgSQLMode;
  56
  57                 # Close/unset connection handle
  58                 $this->close();
  59
  60                 # Debugging hack -- fake cluster
  61                 $realServer = $wgAllDBsAreLocalhost ? 'localhost' : $server;
  62                 $this->mServer = $server;
  63                 $this->mUser = $user;
  64                 $this->mPassword = $password;
  65                 $this->mDBname = $dbName;
  66
  67                 $this->installErrorHandler();
  68                 try {
  69                         $this->mConn = $this->mysqlConnect( $realServer );
  70                 } catch ( Exception $ex ) {
  71                         $this->restoreErrorHandler();
  72                         throw $ex;
  73                 }
  74                 $error = $this->restoreErrorHandler();
  75
  76                 # Always log connection errors
  77                 if ( !$this->mConn ) {
  78                         if ( !$error ) {
  79                                 $error = $this->lastError();
  80                         }
  81                         wfLogDBError(
  82                                 "Error connecting to {db_server}: {error}",
  83                                 $this->getLogContext( array(
  84                                         'method' => __METHOD__,
  85                                         'error' => $error,
  86                                 ) )
  87                         );
  88                         wfDebug( "DB connection error\n" .
  89                                 "Server: $server, User: $user, Password: " .
  90                                 substr( $password, 0, 3 ) . "..., error: " . $error . "\n" );
  91
  92                         $this->reportConnectionError( $error );
  93                 }
  94
  95                 if ( $dbName != '' ) {
  96                         MediaWiki\suppressWarnings();
  97                         $success = $this->selectDB( $dbName );
  98                         MediaWiki\restoreWarnings();
  99                         if ( !$success ) {
 100                                 wfLogDBError(
 101                                         "Error selecting database {db_name} on server {db_server}",
 102                                         $this->getLogContext( array(
 103                                                 'method' => __METHOD__,
 104                                         ) )
 105                                 );
 106                                 wfDebug( "Error selecting database $dbName on server {$this->mServer} " .
 107                                         "from client host " . wfHostname() . "\n" );
 108
 109                                 $this->reportConnectionError( "Error selecting database $dbName" );
 110                         }
 111                 }
 112
 113                 // Tell the server what we're communicating with
 114                 if ( !$this->connectInitCharset() ) {
 115                         $this->reportConnectionError( "Error setting character set" );
 116                 }
 117
 118                 // Abstract over any insane MySQL defaults
 119                 $set = array( 'group_concat_max_len = 262144' );
 120                 // Set SQL mode, default is turning them all off, can be overridden or skipped with null
 121                 if ( is_string( $wgSQLMode ) ) {
 122                         $set[] = 'sql_mode = ' . $this->addQuotes( $wgSQLMode );
 123                 }
 124                 // Set any custom settings defined by site config
 125                 // (e.g. https://dev.mysql.com/doc/refman/4.1/en/innodb-parameters.html)
 126                 foreach ( $this->mSessionVars as $var => $val ) {
 127                         // Escape strings but not numbers to avoid MySQL complaining
 128                         if ( !is_int( $val ) && !is_float( $val ) ) {
 129                                 $val = $this->addQuotes( $val );
 130                         }
 131                         $set[] = $this->addIdentifierQuotes( $var ) . ' = ' . $val;
 132                 }
 133
 134                 if ( $set ) {
 135                         // Use doQuery() to avoid opening implicit transactions (DBO_TRX)
 136                         $success = $this->doQuery( 'SET ' . implode( ', ', $set ) );
 137                         if ( !$success ) {
 138                                 wfLogDBError(
 139                                         'Error setting MySQL variables on server {db_server} (check $wgSQLMode)',
 140                                         $this->getLogContext( array(
 141                                                 'method' => __METHOD__,
 142                                         ) )
 143                                 );
 144                                 $this->reportConnectionError(
 145                                         'Error setting MySQL variables on server {db_server} (check $wgSQLMode)' );
 146                         }
 147                 }
 148
 149                 $this->mOpened = true;
 150
 151                 return true;
 152         }
 153
 154         /**
 155          * Set the character set information right after connection
 156          * @return bool
 157          */
 158         protected function connectInitCharset() {
 159                 global $wgDBmysql5;
 160
 161                 if ( $wgDBmysql5 ) {
 162                         // Tell the server we're communicating with it in UTF-8.
 163                         // This may engage various charset conversions.
 164                         return $this->mysqlSetCharset( 'utf8' );
 165                 } else {
 166                         return $this->mysqlSetCharset( 'binary' );
 167                 }
 168         }
 169
 170         /**
 171          * Open a connection to a MySQL server
 172          *
 173          * @param string $realServer
 174          * @return mixed Raw connection
 175          * @throws DBConnectionError
 176          */
 177         abstract protected function mysqlConnect( $realServer );
 178
 179         /**
 180          * Set the character set of the MySQL link
 181          *
 182          * @param string $charset
 183          * @return bool
 184          */
 185         abstract protected function mysqlSetCharset( $charset );
 186
 187         /**
 188          * @param ResultWrapper|resource $res
 189          * @throws DBUnexpectedError
 190          */
 191         function freeResult( $res ) {
 192                 if ( $res instanceof ResultWrapper ) {
 193                         $res = $res->result;
 194                 }
 195                 MediaWiki\suppressWarnings();
 196                 $ok = $this->mysqlFreeResult( $res );
 197                 MediaWiki\restoreWarnings();
 198                 if ( !$ok ) {
 199                         throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
 200                 }
 201         }
 202
 203         /**
 204          * Free result memory
 205          *
 206          * @param resource $res Raw result
 207          * @return bool
 208          */
 209         abstract protected function mysqlFreeResult( $res );
 210
 211         /**
 212          * @param ResultWrapper|resource $res
 213          * @return stdClass|bool
 214          * @throws DBUnexpectedError
 215          */
 216         function fetchObject( $res ) {
 217                 if ( $res instanceof ResultWrapper ) {
 218                         $res = $res->result;
 219                 }
 220                 MediaWiki\suppressWarnings();
 221                 $row = $this->mysqlFetchObject( $res );
 222                 MediaWiki\restoreWarnings();
 223
 224                 $errno = $this->lastErrno();
 225                 // Unfortunately, mysql_fetch_object does not reset the last errno.
 226                 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
 227                 // these are the only errors mysql_fetch_object can cause.
 228                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 229                 if ( $errno == 2000 || $errno == 2013 ) {
 230                         throw new DBUnexpectedError(
 231                                 $this,
 232                                 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() )
 233                         );
 234                 }
 235
 236                 return $row;
 237         }
 238
 239         /**
 240          * Fetch a result row as an object
 241          *
 242          * @param resource $res Raw result
 243          * @return stdClass
 244          */
 245         abstract protected function mysqlFetchObject( $res );
 246
 247         /**
 248          * @param ResultWrapper|resource $res
 249          * @return array|bool
 250          * @throws DBUnexpectedError
 251          */
 252         function fetchRow( $res ) {
 253                 if ( $res instanceof ResultWrapper ) {
 254                         $res = $res->result;
 255                 }
 256                 MediaWiki\suppressWarnings();
 257                 $row = $this->mysqlFetchArray( $res );
 258                 MediaWiki\restoreWarnings();
 259
 260                 $errno = $this->lastErrno();
 261                 // Unfortunately, mysql_fetch_array does not reset the last errno.
 262                 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
 263                 // these are the only errors mysql_fetch_array can cause.
 264                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 265                 if ( $errno == 2000 || $errno == 2013 ) {
 266                         throw new DBUnexpectedError(
 267                                 $this,
 268                                 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() )
 269                         );
 270                 }
 271
 272                 return $row;
 273         }
 274
 275         /**
 276          * Fetch a result row as an associative and numeric array
 277          *
 278          * @param resource $res Raw result
 279          * @return array
 280          */
 281         abstract protected function mysqlFetchArray( $res );
 282
 283         /**
 284          * @throws DBUnexpectedError
 285          * @param ResultWrapper|resource $res
 286          * @return int
 287          */
 288         function numRows( $res ) {
 289                 if ( $res instanceof ResultWrapper ) {
 290                         $res = $res->result;
 291                 }
 292                 MediaWiki\suppressWarnings();
 293                 $n = $this->mysqlNumRows( $res );
 294                 MediaWiki\restoreWarnings();
 295
 296                 // Unfortunately, mysql_num_rows does not reset the last errno.
 297                 // We are not checking for any errors here, since
 298                 // these are no errors mysql_num_rows can cause.
 299                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 300                 // See https://phabricator.wikimedia.org/T44430
 301                 return $n;
 302         }
 303
 304         /**
 305          * Get number of rows in result
 306          *
 307          * @param resource $res Raw result
 308          * @return int
 309          */
 310         abstract protected function mysqlNumRows( $res );
 311
 312         /**
 313          * @param ResultWrapper|resource $res
 314          * @return int
 315          */
 316         function numFields( $res ) {
 317                 if ( $res instanceof ResultWrapper ) {
 318                         $res = $res->result;
 319                 }
 320
 321                 return $this->mysqlNumFields( $res );
 322         }
 323
 324         /**
 325          * Get number of fields in result
 326          *
 327          * @param resource $res Raw result
 328          * @return int
 329          */
 330         abstract protected function mysqlNumFields( $res );
 331
 332         /**
 333          * @param ResultWrapper|resource $res
 334          * @param int $n
 335          * @return string
 336          */
 337         function fieldName( $res, $n ) {
 338                 if ( $res instanceof ResultWrapper ) {
 339                         $res = $res->result;
 340                 }
 341
 342                 return $this->mysqlFieldName( $res, $n );
 343         }
 344
 345         /**
 346          * Get the name of the specified field in a result
 347          *
 348          * @param ResultWrapper|resource $res
 349          * @param int $n
 350          * @return string
 351          */
 352         abstract protected function mysqlFieldName( $res, $n );
 353
 354         /**
 355          * mysql_field_type() wrapper
 356          * @param ResultWrapper|resource $res
 357          * @param int $n
 358          * @return string
 359          */
 360         public function fieldType( $res, $n ) {
 361                 if ( $res instanceof ResultWrapper ) {
 362                         $res = $res->result;
 363                 }
 364
 365                 return $this->mysqlFieldType( $res, $n );
 366         }
 367
 368         /**
 369          * Get the type of the specified field in a result
 370          *
 371          * @param ResultWrapper|resource $res
 372          * @param int $n
 373          * @return string
 374          */
 375         abstract protected function mysqlFieldType( $res, $n );
 376
 377         /**
 378          * @param ResultWrapper|resource $res
 379          * @param int $row
 380          * @return bool
 381          */
 382         function dataSeek( $res, $row ) {
 383                 if ( $res instanceof ResultWrapper ) {
 384                         $res = $res->result;
 385                 }
 386
 387                 return $this->mysqlDataSeek( $res, $row );
 388         }
 389
 390         /**
 391          * Move internal result pointer
 392          *
 393          * @param ResultWrapper|resource $res
 394          * @param int $row
 395          * @return bool
 396          */
 397         abstract protected function mysqlDataSeek( $res, $row );
 398
 399         /**
 400          * @return string
 401          */
 402         function lastError() {
 403                 if ( $this->mConn ) {
 404                         # Even if it's non-zero, it can still be invalid
 405                         MediaWiki\suppressWarnings();
 406                         $error = $this->mysqlError( $this->mConn );
 407                         if ( !$error ) {
 408                                 $error = $this->mysqlError();
 409                         }
 410                         MediaWiki\restoreWarnings();
 411                 } else {
 412                         $error = $this->mysqlError();
 413                 }
 414                 if ( $error ) {
 415                         $error .= ' (' . $this->mServer . ')';
 416                 }
 417
 418                 return $error;
 419         }
 420
 421         /**
 422          * Returns the text of the error message from previous MySQL operation
 423          *
 424          * @param resource $conn Raw connection
 425          * @return string
 426          */
 427         abstract protected function mysqlError( $conn = null );
 428
 429         /**
 430          * @param string $table
 431          * @param array $uniqueIndexes
 432          * @param array $rows
 433          * @param string $fname
 434          * @return ResultWrapper
 435          */
 436         function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
 437                 return $this->nativeReplace( $table, $rows, $fname );
 438         }
 439
 440         /**
 441          * Estimate rows in dataset
 442          * Returns estimated count, based on EXPLAIN output
 443          * Takes same arguments as Database::select()
 444          *
 445          * @param string|array $table
 446          * @param string|array $vars
 447          * @param string|array $conds
 448          * @param string $fname
 449          * @param string|array $options
 450          * @return bool|int
 451          */
 452         public function estimateRowCount( $table, $vars = '*', $conds = '',
 453                 $fname = __METHOD__, $options = array()
 454         ) {
 455                 $options['EXPLAIN'] = true;
 456                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 457                 if ( $res === false ) {
 458                         return false;
 459                 }
 460                 if ( !$this->numRows( $res ) ) {
 461                         return 0;
 462                 }
 463
 464                 $rows = 1;
 465                 foreach ( $res as $plan ) {
 466                         $rows *= $plan->rows > 0 ? $plan->rows : 1; // avoid resetting to zero
 467                 }
 468
 469                 return (int)$rows;
 470         }
 471
 472         /**
 473          * @param string $table
 474          * @param string $field
 475          * @return bool|MySQLField
 476          */
 477         function fieldInfo( $table, $field ) {
 478                 $table = $this->tableName( $table );
 479                 $res = $this->query( "SELECT * FROM $table LIMIT 1", __METHOD__, true );
 480                 if ( !$res ) {
 481                         return false;
 482                 }
 483                 $n = $this->mysqlNumFields( $res->result );
 484                 for ( $i = 0; $i < $n; $i++ ) {
 485                         $meta = $this->mysqlFetchField( $res->result, $i );
 486                         if ( $field == $meta->name ) {
 487                                 return new MySQLField( $meta );
 488                         }
 489                 }
 490
 491                 return false;
 492         }
 493
 494         /**
 495          * Get column information from a result
 496          *
 497          * @param resource $res Raw result
 498          * @param int $n
 499          * @return stdClass
 500          */
 501         abstract protected function mysqlFetchField( $res, $n );
 502
 503         /**
 504          * Get information about an index into an object
 505          * Returns false if the index does not exist
 506          *
 507          * @param string $table
 508          * @param string $index
 509          * @param string $fname
 510          * @return bool|array|null False or null on failure
 511          */
 512         function indexInfo( $table, $index, $fname = __METHOD__ ) {
 513                 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
 514                 # SHOW INDEX should work for 3.x and up:
 515                 # http://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
 516                 $table = $this->tableName( $table );
 517                 $index = $this->indexName( $index );
 518
 519                 $sql = 'SHOW INDEX FROM ' . $table;
 520                 $res = $this->query( $sql, $fname );
 521
 522                 if ( !$res ) {
 523                         return null;
 524                 }
 525
 526                 $result = array();
 527
 528                 foreach ( $res as $row ) {
 529                         if ( $row->Key_name == $index ) {
 530                                 $result[] = $row;
 531                         }
 532                 }
 533
 534                 return empty( $result ) ? false : $result;
 535         }
 536
 537         /**
 538          * @param string $s
 539          * @return string
 540          */
 541         function strencode( $s ) {
 542                 $sQuoted = $this->mysqlRealEscapeString( $s );
 543
 544                 if ( $sQuoted === false ) {
 545                         $this->ping();
 546                         $sQuoted = $this->mysqlRealEscapeString( $s );
 547                 }
 548
 549                 return $sQuoted;
 550         }
 551
 552         /**
 553          * MySQL uses `backticks` for identifier quoting instead of the sql standard "double quotes".
 554          *
 555          * @param string $s
 556          * @return string
 557          */
 558         public function addIdentifierQuotes( $s ) {
 559                 // Characters in the range \u0001-\uFFFF are valid in a quoted identifier
 560                 // Remove NUL bytes and escape backticks by doubling
 561                 return '`' . str_replace( array( "\0", '`' ), array( '', '``' ), $s ) . '`';
 562         }
 563
 564         /**
 565          * @param string $name
 566          * @return bool
 567          */
 568         public function isQuotedIdentifier( $name ) {
 569                 return strlen( $name ) && $name[0] == '`' && substr( $name, -1, 1 ) == '`';
 570         }
 571
 572         /**
 573          * @return bool
 574          */
 575         function ping() {
 576                 $ping = $this->mysqlPing();
 577                 if ( $ping ) {
 578                         // Connection was good or lost but reconnected...
 579                         // @note: mysqlnd (php 5.6+) does not support this (PHP bug 52561)
 580                         return true;
 581                 }
 582
 583                 // Try a full disconnect/reconnect cycle if ping() failed
 584                 $this->closeConnection();
 585                 $this->mOpened = false;
 586                 $this->mConn = false;
 587                 $this->open( $this->mServer, $this->mUser, $this->mPassword, $this->mDBname );
 588
 589                 return true;
 590         }
 591
 592         /**
 593          * Ping a server connection or reconnect if there is no connection
 594          *
 595          * @return bool
 596          */
 597         abstract protected function mysqlPing();
 598
 599         /**
 600          * Returns slave lag.
 601          *
 602          * This will do a SHOW SLAVE STATUS
 603          *
 604          * @return int
 605          */
 606         function getLag() {
 607                 return $this->getLagFromSlaveStatus();
 608         }
 609
 610         /**
 611          * @return bool|int
 612          */
 613         function getLagFromSlaveStatus() {
 614                 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__ );
 615                 if ( !$res ) {
 616                         return false;
 617                 }
 618                 $row = $res->fetchObject();
 619                 if ( !$row ) {
 620                         return false;
 621                 }
 622                 if ( strval( $row->Seconds_Behind_Master ) === '' ) {
 623                         return false;
 624                 } else {
 625                         return intval( $row->Seconds_Behind_Master );
 626                 }
 627         }
 628
 629         /**
 630          * Wait for the slave to catch up to a given master position.
 631          * @todo Return values for this and base class are rubbish
 632          *
 633          * @param DBMasterPos|MySQLMasterPos $pos
 634          * @param int $timeout The maximum number of seconds to wait for synchronisation
 635          * @return int Zero if the slave was past that position already,
 636          *   greater than zero if we waited for some period of time, less than
 637          *   zero if we timed out.
 638          */
 639         function masterPosWait( DBMasterPos $pos, $timeout ) {
 640                 if ( $this->lastKnownSlavePos && $this->lastKnownSlavePos->hasReached( $pos ) ) {
 641                         return '0'; // http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html
 642                 }
 643
 644                 # Commit any open transactions
 645                 $this->commit( __METHOD__, 'flush' );
 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                 return $status;
 662         }
 663
 664         /**
 665          * Get the position of the master from SHOW SLAVE STATUS
 666          *
 667          * @return MySQLMasterPos|bool
 668          */
 669         function getSlavePos() {
 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                 $res = $this->query( 'SHOW MASTER STATUS', 'DatabaseBase::getMasterPos' );
 691                 $row = $this->fetchObject( $res );
 692
 693                 if ( $row ) {
 694                         return new MySQLMasterPos( $row->File, $row->Position );
 695                 } else {
 696                         return false;
 697                 }
 698         }
 699
 700         /**
 701          * @param string $index
 702          * @return string
 703          */
 704         function useIndexClause( $index ) {
 705                 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
 706         }
 707
 708         /**
 709          * @return string
 710          */
 711         function lowPriorityOption() {
 712                 return 'LOW_PRIORITY';
 713         }
 714
 715         /**
 716          * @return string
 717          */
 718         public function getSoftwareLink() {
 719                 // MariaDB includes its name in its version string; this is how MariaDB's version of
 720                 // the mysql command-line client identifies MariaDB servers (see mariadb_connection()
 721                 // in libmysql/libmysql.c).
 722                 $version = $this->getServerVersion();
 723                 if ( strpos( $version, 'MariaDB' ) !== false || strpos( $version, '-maria-' ) !== false ) {
 724                         return '[{{int:version-db-mariadb-url}} MariaDB]';
 725                 }
 726
 727                 // Percona Server's version suffix is not very distinctive, and @@version_comment
 728                 // doesn't give the necessary info for source builds, so assume the server is MySQL.
 729                 // (Even Percona's version of mysql doesn't try to make the distinction.)
 730                 return '[{{int:version-db-mysql-url}} MySQL]';
 731         }
 732
 733         /**
 734          * @return string
 735          */
 736         public function getServerVersion() {
 737                 // Not using mysql_get_server_info() or similar for consistency: in the handshake,
 738                 // MariaDB 10 adds the prefix "5.5.5-", and only some newer client libraries strip
 739                 // it off (see RPL_VERSION_HACK in include/mysql_com.h).
 740                 if ( $this->serverVersion === null ) {
 741                         $this->serverVersion = $this->selectField( '', 'VERSION()', '', __METHOD__ );
 742                 }
 743                 return $this->serverVersion;
 744         }
 745
 746         /**
 747          * @param array $options
 748          */
 749         public function setSessionOptions( array $options ) {
 750                 if ( isset( $options['connTimeout'] ) ) {
 751                         $timeout = (int)$options['connTimeout'];
 752                         $this->query( "SET net_read_timeout=$timeout" );
 753                         $this->query( "SET net_write_timeout=$timeout" );
 754                 }
 755         }
 756
 757         /**
 758          * @param string $sql
 759          * @param string $newLine
 760          * @return bool
 761          */
 762         public function streamStatementEnd( &$sql, &$newLine ) {
 763                 if ( strtoupper( substr( $newLine, 0, 9 ) ) == 'DELIMITER' ) {
 764                         preg_match( '/^DELIMITER\s+(\S+)/', $newLine, $m );
 765                         $this->delimiter = $m[1];
 766                         $newLine = '';
 767                 }
 768
 769                 return parent::streamStatementEnd( $sql, $newLine );
 770         }
 771
 772         /**
 773          * Check to see if a named lock is available. This is non-blocking.
 774          *
 775          * @param string $lockName Name of lock to poll
 776          * @param string $method Name of method calling us
 777          * @return bool
 778          * @since 1.20
 779          */
 780         public function lockIsFree( $lockName, $method ) {
 781                 $lockName = $this->addQuotes( $lockName );
 782                 $result = $this->query( "SELECT IS_FREE_LOCK($lockName) AS lockstatus", $method );
 783                 $row = $this->fetchObject( $result );
 784
 785                 return ( $row->lockstatus == 1 );
 786         }
 787
 788         /**
 789          * @param string $lockName
 790          * @param string $method
 791          * @param int $timeout
 792          * @return bool
 793          */
 794         public function lock( $lockName, $method, $timeout = 5 ) {
 795                 $lockName = $this->addQuotes( $lockName );
 796                 $result = $this->query( "SELECT GET_LOCK($lockName, $timeout) AS lockstatus", $method );
 797                 $row = $this->fetchObject( $result );
 798
 799                 if ( $row->lockstatus == 1 ) {
 800                         return true;
 801                 } else {
 802                         wfDebug( __METHOD__ . " failed to acquire lock\n" );
 803
 804                         return false;
 805                 }
 806         }
 807
 808         /**
 809          * FROM MYSQL DOCS:
 810          * http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
 811          * @param string $lockName
 812          * @param string $method
 813          * @return bool
 814          */
 815         public function unlock( $lockName, $method ) {
 816                 $lockName = $this->addQuotes( $lockName );
 817                 $result = $this->query( "SELECT RELEASE_LOCK($lockName) as lockstatus", $method );
 818                 $row = $this->fetchObject( $result );
 819
 820                 return ( $row->lockstatus == 1 );
 821         }
 822
 823         public function namedLocksEnqueue() {
 824                 return true;
 825         }
 826
 827         /**
 828          * @param array $read
 829          * @param array $write
 830          * @param string $method
 831          * @param bool $lowPriority
 832          * @return bool
 833          */
 834         public function lockTables( $read, $write, $method, $lowPriority = true ) {
 835                 $items = array();
 836
 837                 foreach ( $write as $table ) {
 838                         $tbl = $this->tableName( $table ) .
 839                                 ( $lowPriority ? ' LOW_PRIORITY' : '' ) .
 840                                 ' WRITE';
 841                         $items[] = $tbl;
 842                 }
 843                 foreach ( $read as $table ) {
 844                         $items[] = $this->tableName( $table ) . ' READ';
 845                 }
 846                 $sql = "LOCK TABLES " . implode( ',', $items );
 847                 $this->query( $sql, $method );
 848
 849                 return true;
 850         }
 851
 852         /**
 853          * @param string $method
 854          * @return bool
 855          */
 856         public function unlockTables( $method ) {
 857                 $this->query( "UNLOCK TABLES", $method );
 858
 859                 return true;
 860         }
 861
 862         /**
 863          * Get search engine class. All subclasses of this
 864          * need to implement this if they wish to use searching.
 865          *
 866          * @return string
 867          */
 868         public function getSearchEngine() {
 869                 return 'SearchMySQL';
 870         }
 871
 872         /**
 873          * @param bool $value
 874          */
 875         public function setBigSelects( $value = true ) {
 876                 if ( $value === 'default' ) {
 877                         if ( $this->mDefaultBigSelects === null ) {
 878                                 # Function hasn't been called before so it must already be set to the default
 879                                 return;
 880                         } else {
 881                                 $value = $this->mDefaultBigSelects;
 882                         }
 883                 } elseif ( $this->mDefaultBigSelects === null ) {
 884                         $this->mDefaultBigSelects =
 885                                 (bool)$this->selectField( false, '@@sql_big_selects', '', __METHOD__ );
 886                 }
 887                 $encValue = $value ? '1' : '0';
 888                 $this->query( "SET sql_big_selects=$encValue", __METHOD__ );
 889         }
 890
 891         /**
 892          * DELETE where the condition is a join. MySql uses multi-table deletes.
 893          * @param string $delTable
 894          * @param string $joinTable
 895          * @param string $delVar
 896          * @param string $joinVar
 897          * @param array|string $conds
 898          * @param bool|string $fname
 899          * @throws DBUnexpectedError
 900          * @return bool|ResultWrapper
 901          */
 902         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = __METHOD__ ) {
 903                 if ( !$conds ) {
 904                         throw new DBUnexpectedError( $this, 'DatabaseBase::deleteJoin() called with empty $conds' );
 905                 }
 906
 907                 $delTable = $this->tableName( $delTable );
 908                 $joinTable = $this->tableName( $joinTable );
 909                 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
 910
 911                 if ( $conds != '*' ) {
 912                         $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
 913                 }
 914
 915                 return $this->query( $sql, $fname );
 916         }
 917
 918         /**
 919          * @param string $table
 920          * @param array $rows
 921          * @param array $uniqueIndexes
 922          * @param array $set
 923          * @param string $fname
 924          * @return bool
 925          */
 926         public function upsert( $table, array $rows, array $uniqueIndexes,
 927                 array $set, $fname = __METHOD__
 928         ) {
 929                 if ( !count( $rows ) ) {
 930                         return true; // nothing to do
 931                 }
 932
 933                 if ( !is_array( reset( $rows ) ) ) {
 934                         $rows = array( $rows );
 935                 }
 936
 937                 $table = $this->tableName( $table );
 938                 $columns = array_keys( $rows[0] );
 939
 940                 $sql = "INSERT INTO $table (" . implode( ',', $columns ) . ') VALUES ';
 941                 $rowTuples = array();
 942                 foreach ( $rows as $row ) {
 943                         $rowTuples[] = '(' . $this->makeList( $row ) . ')';
 944                 }
 945                 $sql .= implode( ',', $rowTuples );
 946                 $sql .= " ON DUPLICATE KEY UPDATE " . $this->makeList( $set, LIST_SET );
 947
 948                 return (bool)$this->query( $sql, $fname );
 949         }
 950
 951         /**
 952          * Determines how long the server has been up
 953          *
 954          * @return int
 955          */
 956         function getServerUptime() {
 957                 $vars = $this->getMysqlStatus( 'Uptime' );
 958
 959                 return (int)$vars['Uptime'];
 960         }
 961
 962         /**
 963          * Determines if the last failure was due to a deadlock
 964          *
 965          * @return bool
 966          */
 967         function wasDeadlock() {
 968                 return $this->lastErrno() == 1213;
 969         }
 970
 971         /**
 972          * Determines if the last failure was due to a lock timeout
 973          *
 974          * @return bool
 975          */
 976         function wasLockTimeout() {
 977                 return $this->lastErrno() == 1205;
 978         }
 979
 980         /**
 981          * Determines if the last query error was something that should be dealt
 982          * with by pinging the connection and reissuing the query
 983          *
 984          * @return bool
 985          */
 986         function wasErrorReissuable() {
 987                 return $this->lastErrno() == 2013 || $this->lastErrno() == 2006;
 988         }
 989
 990         /**
 991          * Determines if the last failure was due to the database being read-only.
 992          *
 993          * @return bool
 994          */
 995         function wasReadOnlyError() {
 996                 return $this->lastErrno() == 1223 ||
 997                         ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
 998         }
 999
1000         function wasConnectionError( $errno ) {
1001                 return $errno == 2013 || $errno == 2006;
1002         }
1003
1004         /**
1005          * Get the underlying binding handle, mConn
1006          *
1007          * Makes sure that mConn is set (disconnects and ping() failure can unset it).
1008          * This catches broken callers than catch and ignore disconnection exceptions.
1009          * Unlike checking isOpen(), this is safe to call inside of open().
1010          *
1011          * @return resource|object
1012          * @throws DBUnexpectedError
1013          * @since 1.26
1014          */
1015         protected function getBindingHandle() {
1016                 if ( !$this->mConn ) {
1017                         throw new DBUnexpectedError(
1018                                 $this,
1019                                 'DB connection was already closed or the connection dropped.'
1020                         );
1021                 }
1022
1023                 return $this->mConn;
1024         }
1025
1026         /**
1027          * @param string $oldName
1028          * @param string $newName
1029          * @param bool $temporary
1030          * @param string $fname
1031          * @return bool
1032          */
1033         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
1034                 $tmp = $temporary ? 'TEMPORARY ' : '';
1035                 $newName = $this->addIdentifierQuotes( $newName );
1036                 $oldName = $this->addIdentifierQuotes( $oldName );
1037                 $query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
1038
1039                 return $this->query( $query, $fname );
1040         }
1041
1042         /**
1043          * List all tables on the database
1044          *
1045          * @param string $prefix Only show tables with this prefix, e.g. mw_
1046          * @param string $fname Calling function name
1047          * @return array
1048          */
1049         function listTables( $prefix = null, $fname = __METHOD__ ) {
1050                 $result = $this->query( "SHOW TABLES", $fname );
1051
1052                 $endArray = array();
1053
1054                 foreach ( $result as $table ) {
1055                         $vars = get_object_vars( $table );
1056                         $table = array_pop( $vars );
1057
1058                         if ( !$prefix || strpos( $table, $prefix ) === 0 ) {
1059                                 $endArray[] = $table;
1060                         }
1061                 }
1062
1063                 return $endArray;
1064         }
1065
1066         /**
1067          * @param string $tableName
1068          * @param string $fName
1069          * @return bool|ResultWrapper
1070          */
1071         public function dropTable( $tableName, $fName = __METHOD__ ) {
1072                 if ( !$this->tableExists( $tableName, $fName ) ) {
1073                         return false;
1074                 }
1075
1076                 return $this->query( "DROP TABLE IF EXISTS " . $this->tableName( $tableName ), $fName );
1077         }
1078
1079         /**
1080          * @return array
1081          */
1082         protected function getDefaultSchemaVars() {
1083                 $vars = parent::getDefaultSchemaVars();
1084                 $vars['wgDBTableOptions'] = str_replace( 'TYPE', 'ENGINE', $GLOBALS['wgDBTableOptions'] );
1085                 $vars['wgDBTableOptions'] = str_replace(
1086                         'CHARSET=mysql4',
1087                         'CHARSET=binary',
1088                         $vars['wgDBTableOptions']
1089                 );
1090
1091                 return $vars;
1092         }
1093
1094         /**
1095          * Get status information from SHOW STATUS in an associative array
1096          *
1097          * @param string $which
1098          * @return array
1099          */
1100         function getMysqlStatus( $which = "%" ) {
1101                 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
1102                 $status = array();
1103
1104                 foreach ( $res as $row ) {
1105                         $status[$row->Variable_name] = $row->Value;
1106                 }
1107
1108                 return $status;
1109         }
1110
1111         /**
1112          * Lists VIEWs in the database
1113          *
1114          * @param string $prefix Only show VIEWs with this prefix, eg.
1115          * unit_test_, or $wgDBprefix. Default: null, would return all views.
1116          * @param string $fname Name of calling function
1117          * @return array
1118          * @since 1.22
1119          */
1120         public function listViews( $prefix = null, $fname = __METHOD__ ) {
1121
1122                 if ( !isset( $this->allViews ) ) {
1123
1124                         // The name of the column containing the name of the VIEW
1125                         $propertyName = 'Tables_in_' . $this->mDBname;
1126
1127                         // Query for the VIEWS
1128                         $result = $this->query( 'SHOW FULL TABLES WHERE TABLE_TYPE = "VIEW"' );
1129                         $this->allViews = array();
1130                         while ( ( $row = $this->fetchRow( $result ) ) !== false ) {
1131                                 array_push( $this->allViews, $row[$propertyName] );
1132                         }
1133                 }
1134
1135                 if ( is_null( $prefix ) || $prefix === '' ) {
1136                         return $this->allViews;
1137                 }
1138
1139                 $filteredViews = array();
1140                 foreach ( $this->allViews as $viewName ) {
1141                         // Does the name of this VIEW start with the table-prefix?
1142                         if ( strpos( $viewName, $prefix ) === 0 ) {
1143                                 array_push( $filteredViews, $viewName );
1144                         }
1145                 }
1146
1147                 return $filteredViews;
1148         }
1149
1150         /**
1151          * Differentiates between a TABLE and a VIEW.
1152          *
1153          * @param string $name Name of the TABLE/VIEW to test
1154          * @param string $prefix
1155          * @return bool
1156          * @since 1.22
1157          */
1158         public function isView( $name, $prefix = null ) {
1159                 return in_array( $name, $this->listViews( $prefix ) );
1160         }
1161 }
1162
1163 /**
1164  * Utility class.
1165  * @ingroup Database
1166  */
1167 class MySQLField implements Field {
1168         private $name, $tablename, $default, $max_length, $nullable,
1169                 $is_pk, $is_unique, $is_multiple, $is_key, $type, $binary,
1170                 $is_numeric, $is_blob, $is_unsigned, $is_zerofill;
1171
1172         function __construct( $info ) {
1173                 $this->name = $info->name;
1174                 $this->tablename = $info->table;
1175                 $this->default = $info->def;
1176                 $this->max_length = $info->max_length;
1177                 $this->nullable = !$info->not_null;
1178                 $this->is_pk = $info->primary_key;
1179                 $this->is_unique = $info->unique_key;
1180                 $this->is_multiple = $info->multiple_key;
1181                 $this->is_key = ( $this->is_pk || $this->is_unique || $this->is_multiple );
1182                 $this->type = $info->type;
1183                 $this->binary = isset( $info->binary ) ? $info->binary : false;
1184                 $this->is_numeric = isset( $info->numeric ) ? $info->numeric : false;
1185                 $this->is_blob = isset( $info->blob ) ? $info->blob : false;
1186                 $this->is_unsigned = isset( $info->unsigned ) ? $info->unsigned : false;
1187                 $this->is_zerofill = isset( $info->zerofill ) ? $info->zerofill : false;
1188         }
1189
1190         /**
1191          * @return string
1192          */
1193         function name() {
1194                 return $this->name;
1195         }
1196
1197         /**
1198          * @return string
1199          */
1200         function tableName() {
1201                 return $this->tableName;
1202         }
1203
1204         /**
1205          * @return string
1206          */
1207         function type() {
1208                 return $this->type;
1209         }
1210
1211         /**
1212          * @return bool
1213          */
1214         function isNullable() {
1215                 return $this->nullable;
1216         }
1217
1218         function defaultValue() {
1219                 return $this->default;
1220         }
1221
1222         /**
1223          * @return bool
1224          */
1225         function isKey() {
1226                 return $this->is_key;
1227         }
1228
1229         /**
1230          * @return bool
1231          */
1232         function isMultipleKey() {
1233                 return $this->is_multiple;
1234         }
1235
1236         /**
1237          * @return bool
1238          */
1239         function isBinary() {
1240                 return $this->binary;
1241         }
1242
1243         /**
1244          * @return bool
1245          */
1246         function isNumeric() {
1247                 return $this->is_numeric;
1248         }
1249
1250         /**
1251          * @return bool
1252          */
1253         function isBlob() {
1254                 return $this->is_blob;
1255         }
1256
1257         /**
1258          * @return bool
1259          */
1260         function isUnsigned() {
1261                 return $this->is_unsigned;
1262         }
1263
1264         /**
1265          * @return bool
1266          */
1267         function isZerofill() {
1268                 return $this->is_zerofill;
1269         }
1270 }
1271
1272 class MySQLMasterPos implements DBMasterPos {
1273         /** @var string */
1274         public $file;
1275         /** @var int Position */
1276         public $pos;
1277         /** @var float UNIX timestamp */
1278         public $asOfTime = 0.0;
1279
1280         function __construct( $file, $pos ) {
1281                 $this->file = $file;
1282                 $this->pos = $pos;
1283                 $this->asOfTime = microtime( true );
1284         }
1285
1286         function __toString() {
1287                 // e.g db1034-bin.000976/843431247
1288                 return "{$this->file}/{$this->pos}";
1289         }
1290
1291         /**
1292          * @return array|bool (int, int)
1293          */
1294         protected function getCoordinates() {
1295                 $m = array();
1296                 if ( preg_match( '!\.(\d+)/(\d+)$!', (string)$this, $m ) ) {
1297                         return array( (int)$m[1], (int)$m[2] );
1298                 }
1299
1300                 return false;
1301         }
1302
1303         function hasReached( MySQLMasterPos $pos ) {
1304                 $thisPos = $this->getCoordinates();
1305                 $thatPos = $pos->getCoordinates();
1306
1307                 return ( $thisPos && $thatPos && $thisPos >= $thatPos );
1308         }
1309
1310         function asOfTime() {
1311                 return $this->asOfTime;
1312         }
1313 }