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         /** @var string Method to detect slave lag */
  36         protected $lagDetectionMethod;
  37
  38         /** @var BagOStuff APC cache */
  39         protected $srvCache;
  40
  41         /** @var string|null */
  42         private $serverVersion = null;
  43
  44         /**
  45          * Additional $params include:
  46          *   - lagDetectionMethod : set to one of (Seconds_Behind_Master,pt-heartbeat).
  47          *                          pt-heartbeat assumes the table is at heartbeat.heartbeat
  48          *                          and uses UTC timestamps in the heartbeat.ts column.
  49          *                          (https://www.percona.com/doc/percona-toolkit/2.2/pt-heartbeat.html)
  50          * @param array $params
  51          */
  52         function __construct( array $params ) {
  53                 parent::__construct( $params );
  54
  55                 $this->lagDetectionMethod = isset( $params['lagDetectionMethod'] )
  56                         ? $params['lagDetectionMethod']
  57                         : 'Seconds_Behind_Master';
  58
  59                 $this->srvCache = ObjectCache::newAccelerator( 'hash' );
  60         }
  61
  62         /**
  63          * @return string
  64          */
  65         function getType() {
  66                 return 'mysql';
  67         }
  68
  69         /**
  70          * @param string $server
  71          * @param string $user
  72          * @param string $password
  73          * @param string $dbName
  74          * @throws Exception|DBConnectionError
  75          * @return bool
  76          */
  77         function open( $server, $user, $password, $dbName ) {
  78                 global $wgAllDBsAreLocalhost, $wgSQLMode;
  79
  80                 # Close/unset connection handle
  81                 $this->close();
  82
  83                 # Debugging hack -- fake cluster
  84                 $realServer = $wgAllDBsAreLocalhost ? 'localhost' : $server;
  85                 $this->mServer = $server;
  86                 $this->mUser = $user;
  87                 $this->mPassword = $password;
  88                 $this->mDBname = $dbName;
  89
  90                 $this->installErrorHandler();
  91                 try {
  92                         $this->mConn = $this->mysqlConnect( $realServer );
  93                 } catch ( Exception $ex ) {
  94                         $this->restoreErrorHandler();
  95                         throw $ex;
  96                 }
  97                 $error = $this->restoreErrorHandler();
  98
  99                 # Always log connection errors
 100                 if ( !$this->mConn ) {
 101                         if ( !$error ) {
 102                                 $error = $this->lastError();
 103                         }
 104                         wfLogDBError(
 105                                 "Error connecting to {db_server}: {error}",
 106                                 $this->getLogContext( array(
 107                                         'method' => __METHOD__,
 108                                         'error' => $error,
 109                                 ) )
 110                         );
 111                         wfDebug( "DB connection error\n" .
 112                                 "Server: $server, User: $user, Password: " .
 113                                 substr( $password, 0, 3 ) . "..., error: " . $error . "\n" );
 114
 115                         $this->reportConnectionError( $error );
 116                 }
 117
 118                 if ( $dbName != '' ) {
 119                         MediaWiki\suppressWarnings();
 120                         $success = $this->selectDB( $dbName );
 121                         MediaWiki\restoreWarnings();
 122                         if ( !$success ) {
 123                                 wfLogDBError(
 124                                         "Error selecting database {db_name} on server {db_server}",
 125                                         $this->getLogContext( array(
 126                                                 'method' => __METHOD__,
 127                                         ) )
 128                                 );
 129                                 wfDebug( "Error selecting database $dbName on server {$this->mServer} " .
 130                                         "from client host " . wfHostname() . "\n" );
 131
 132                                 $this->reportConnectionError( "Error selecting database $dbName" );
 133                         }
 134                 }
 135
 136                 // Tell the server what we're communicating with
 137                 if ( !$this->connectInitCharset() ) {
 138                         $this->reportConnectionError( "Error setting character set" );
 139                 }
 140
 141                 // Abstract over any insane MySQL defaults
 142                 $set = array( 'group_concat_max_len = 262144' );
 143                 // Set SQL mode, default is turning them all off, can be overridden or skipped with null
 144                 if ( is_string( $wgSQLMode ) ) {
 145                         $set[] = 'sql_mode = ' . $this->addQuotes( $wgSQLMode );
 146                 }
 147                 // Set any custom settings defined by site config
 148                 // (e.g. https://dev.mysql.com/doc/refman/4.1/en/innodb-parameters.html)
 149                 foreach ( $this->mSessionVars as $var => $val ) {
 150                         // Escape strings but not numbers to avoid MySQL complaining
 151                         if ( !is_int( $val ) && !is_float( $val ) ) {
 152                                 $val = $this->addQuotes( $val );
 153                         }
 154                         $set[] = $this->addIdentifierQuotes( $var ) . ' = ' . $val;
 155                 }
 156
 157                 if ( $set ) {
 158                         // Use doQuery() to avoid opening implicit transactions (DBO_TRX)
 159                         $success = $this->doQuery( 'SET ' . implode( ', ', $set ) );
 160                         if ( !$success ) {
 161                                 wfLogDBError(
 162                                         'Error setting MySQL variables on server {db_server} (check $wgSQLMode)',
 163                                         $this->getLogContext( array(
 164                                                 'method' => __METHOD__,
 165                                         ) )
 166                                 );
 167                                 $this->reportConnectionError(
 168                                         'Error setting MySQL variables on server {db_server} (check $wgSQLMode)' );
 169                         }
 170                 }
 171
 172                 $this->mOpened = true;
 173
 174                 return true;
 175         }
 176
 177         /**
 178          * Set the character set information right after connection
 179          * @return bool
 180          */
 181         protected function connectInitCharset() {
 182                 global $wgDBmysql5;
 183
 184                 if ( $wgDBmysql5 ) {
 185                         // Tell the server we're communicating with it in UTF-8.
 186                         // This may engage various charset conversions.
 187                         return $this->mysqlSetCharset( 'utf8' );
 188                 } else {
 189                         return $this->mysqlSetCharset( 'binary' );
 190                 }
 191         }
 192
 193         /**
 194          * Open a connection to a MySQL server
 195          *
 196          * @param string $realServer
 197          * @return mixed Raw connection
 198          * @throws DBConnectionError
 199          */
 200         abstract protected function mysqlConnect( $realServer );
 201
 202         /**
 203          * Set the character set of the MySQL link
 204          *
 205          * @param string $charset
 206          * @return bool
 207          */
 208         abstract protected function mysqlSetCharset( $charset );
 209
 210         /**
 211          * @param ResultWrapper|resource $res
 212          * @throws DBUnexpectedError
 213          */
 214         function freeResult( $res ) {
 215                 if ( $res instanceof ResultWrapper ) {
 216                         $res = $res->result;
 217                 }
 218                 MediaWiki\suppressWarnings();
 219                 $ok = $this->mysqlFreeResult( $res );
 220                 MediaWiki\restoreWarnings();
 221                 if ( !$ok ) {
 222                         throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
 223                 }
 224         }
 225
 226         /**
 227          * Free result memory
 228          *
 229          * @param resource $res Raw result
 230          * @return bool
 231          */
 232         abstract protected function mysqlFreeResult( $res );
 233
 234         /**
 235          * @param ResultWrapper|resource $res
 236          * @return stdClass|bool
 237          * @throws DBUnexpectedError
 238          */
 239         function fetchObject( $res ) {
 240                 if ( $res instanceof ResultWrapper ) {
 241                         $res = $res->result;
 242                 }
 243                 MediaWiki\suppressWarnings();
 244                 $row = $this->mysqlFetchObject( $res );
 245                 MediaWiki\restoreWarnings();
 246
 247                 $errno = $this->lastErrno();
 248                 // Unfortunately, mysql_fetch_object does not reset the last errno.
 249                 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
 250                 // these are the only errors mysql_fetch_object can cause.
 251                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 252                 if ( $errno == 2000 || $errno == 2013 ) {
 253                         throw new DBUnexpectedError(
 254                                 $this,
 255                                 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() )
 256                         );
 257                 }
 258
 259                 return $row;
 260         }
 261
 262         /**
 263          * Fetch a result row as an object
 264          *
 265          * @param resource $res Raw result
 266          * @return stdClass
 267          */
 268         abstract protected function mysqlFetchObject( $res );
 269
 270         /**
 271          * @param ResultWrapper|resource $res
 272          * @return array|bool
 273          * @throws DBUnexpectedError
 274          */
 275         function fetchRow( $res ) {
 276                 if ( $res instanceof ResultWrapper ) {
 277                         $res = $res->result;
 278                 }
 279                 MediaWiki\suppressWarnings();
 280                 $row = $this->mysqlFetchArray( $res );
 281                 MediaWiki\restoreWarnings();
 282
 283                 $errno = $this->lastErrno();
 284                 // Unfortunately, mysql_fetch_array does not reset the last errno.
 285                 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
 286                 // these are the only errors mysql_fetch_array can cause.
 287                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 288                 if ( $errno == 2000 || $errno == 2013 ) {
 289                         throw new DBUnexpectedError(
 290                                 $this,
 291                                 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() )
 292                         );
 293                 }
 294
 295                 return $row;
 296         }
 297
 298         /**
 299          * Fetch a result row as an associative and numeric array
 300          *
 301          * @param resource $res Raw result
 302          * @return array
 303          */
 304         abstract protected function mysqlFetchArray( $res );
 305
 306         /**
 307          * @throws DBUnexpectedError
 308          * @param ResultWrapper|resource $res
 309          * @return int
 310          */
 311         function numRows( $res ) {
 312                 if ( $res instanceof ResultWrapper ) {
 313                         $res = $res->result;
 314                 }
 315                 MediaWiki\suppressWarnings();
 316                 $n = $this->mysqlNumRows( $res );
 317                 MediaWiki\restoreWarnings();
 318
 319                 // Unfortunately, mysql_num_rows does not reset the last errno.
 320                 // We are not checking for any errors here, since
 321                 // these are no errors mysql_num_rows can cause.
 322                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 323                 // See https://phabricator.wikimedia.org/T44430
 324                 return $n;
 325         }
 326
 327         /**
 328          * Get number of rows in result
 329          *
 330          * @param resource $res Raw result
 331          * @return int
 332          */
 333         abstract protected function mysqlNumRows( $res );
 334
 335         /**
 336          * @param ResultWrapper|resource $res
 337          * @return int
 338          */
 339         function numFields( $res ) {
 340                 if ( $res instanceof ResultWrapper ) {
 341                         $res = $res->result;
 342                 }
 343
 344                 return $this->mysqlNumFields( $res );
 345         }
 346
 347         /**
 348          * Get number of fields in result
 349          *
 350          * @param resource $res Raw result
 351          * @return int
 352          */
 353         abstract protected function mysqlNumFields( $res );
 354
 355         /**
 356          * @param ResultWrapper|resource $res
 357          * @param int $n
 358          * @return string
 359          */
 360         function fieldName( $res, $n ) {
 361                 if ( $res instanceof ResultWrapper ) {
 362                         $res = $res->result;
 363                 }
 364
 365                 return $this->mysqlFieldName( $res, $n );
 366         }
 367
 368         /**
 369          * Get the name 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 mysqlFieldName( $res, $n );
 376
 377         /**
 378          * mysql_field_type() wrapper
 379          * @param ResultWrapper|resource $res
 380          * @param int $n
 381          * @return string
 382          */
 383         public function fieldType( $res, $n ) {
 384                 if ( $res instanceof ResultWrapper ) {
 385                         $res = $res->result;
 386                 }
 387
 388                 return $this->mysqlFieldType( $res, $n );
 389         }
 390
 391         /**
 392          * Get the type of the specified field in a result
 393          *
 394          * @param ResultWrapper|resource $res
 395          * @param int $n
 396          * @return string
 397          */
 398         abstract protected function mysqlFieldType( $res, $n );
 399
 400         /**
 401          * @param ResultWrapper|resource $res
 402          * @param int $row
 403          * @return bool
 404          */
 405         function dataSeek( $res, $row ) {
 406                 if ( $res instanceof ResultWrapper ) {
 407                         $res = $res->result;
 408                 }
 409
 410                 return $this->mysqlDataSeek( $res, $row );
 411         }
 412
 413         /**
 414          * Move internal result pointer
 415          *
 416          * @param ResultWrapper|resource $res
 417          * @param int $row
 418          * @return bool
 419          */
 420         abstract protected function mysqlDataSeek( $res, $row );
 421
 422         /**
 423          * @return string
 424          */
 425         function lastError() {
 426                 if ( $this->mConn ) {
 427                         # Even if it's non-zero, it can still be invalid
 428                         MediaWiki\suppressWarnings();
 429                         $error = $this->mysqlError( $this->mConn );
 430                         if ( !$error ) {
 431                                 $error = $this->mysqlError();
 432                         }
 433                         MediaWiki\restoreWarnings();
 434                 } else {
 435                         $error = $this->mysqlError();
 436                 }
 437                 if ( $error ) {
 438                         $error .= ' (' . $this->mServer . ')';
 439                 }
 440
 441                 return $error;
 442         }
 443
 444         /**
 445          * Returns the text of the error message from previous MySQL operation
 446          *
 447          * @param resource $conn Raw connection
 448          * @return string
 449          */
 450         abstract protected function mysqlError( $conn = null );
 451
 452         /**
 453          * @param string $table
 454          * @param array $uniqueIndexes
 455          * @param array $rows
 456          * @param string $fname
 457          * @return ResultWrapper
 458          */
 459         function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
 460                 return $this->nativeReplace( $table, $rows, $fname );
 461         }
 462
 463         /**
 464          * Estimate rows in dataset
 465          * Returns estimated count, based on EXPLAIN output
 466          * Takes same arguments as Database::select()
 467          *
 468          * @param string|array $table
 469          * @param string|array $vars
 470          * @param string|array $conds
 471          * @param string $fname
 472          * @param string|array $options
 473          * @return bool|int
 474          */
 475         public function estimateRowCount( $table, $vars = '*', $conds = '',
 476                 $fname = __METHOD__, $options = array()
 477         ) {
 478                 $options['EXPLAIN'] = true;
 479                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 480                 if ( $res === false ) {
 481                         return false;
 482                 }
 483                 if ( !$this->numRows( $res ) ) {
 484                         return 0;
 485                 }
 486
 487                 $rows = 1;
 488                 foreach ( $res as $plan ) {
 489                         $rows *= $plan->rows > 0 ? $plan->rows : 1; // avoid resetting to zero
 490                 }
 491
 492                 return (int)$rows;
 493         }
 494
 495         /**
 496          * @param string $table
 497          * @param string $field
 498          * @return bool|MySQLField
 499          */
 500         function fieldInfo( $table, $field ) {
 501                 $table = $this->tableName( $table );
 502                 $res = $this->query( "SELECT * FROM $table LIMIT 1", __METHOD__, true );
 503                 if ( !$res ) {
 504                         return false;
 505                 }
 506                 $n = $this->mysqlNumFields( $res->result );
 507                 for ( $i = 0; $i < $n; $i++ ) {
 508                         $meta = $this->mysqlFetchField( $res->result, $i );
 509                         if ( $field == $meta->name ) {
 510                                 return new MySQLField( $meta );
 511                         }
 512                 }
 513
 514                 return false;
 515         }
 516
 517         /**
 518          * Get column information from a result
 519          *
 520          * @param resource $res Raw result
 521          * @param int $n
 522          * @return stdClass
 523          */
 524         abstract protected function mysqlFetchField( $res, $n );
 525
 526         /**
 527          * Get information about an index into an object
 528          * Returns false if the index does not exist
 529          *
 530          * @param string $table
 531          * @param string $index
 532          * @param string $fname
 533          * @return bool|array|null False or null on failure
 534          */
 535         function indexInfo( $table, $index, $fname = __METHOD__ ) {
 536                 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
 537                 # SHOW INDEX should work for 3.x and up:
 538                 # http://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
 539                 $table = $this->tableName( $table );
 540                 $index = $this->indexName( $index );
 541
 542                 $sql = 'SHOW INDEX FROM ' . $table;
 543                 $res = $this->query( $sql, $fname );
 544
 545                 if ( !$res ) {
 546                         return null;
 547                 }
 548
 549                 $result = array();
 550
 551                 foreach ( $res as $row ) {
 552                         if ( $row->Key_name == $index ) {
 553                                 $result[] = $row;
 554                         }
 555                 }
 556
 557                 return empty( $result ) ? false : $result;
 558         }
 559
 560         /**
 561          * @param string $s
 562          * @return string
 563          */
 564         function strencode( $s ) {
 565                 $sQuoted = $this->mysqlRealEscapeString( $s );
 566
 567                 if ( $sQuoted === false ) {
 568                         $this->ping();
 569                         $sQuoted = $this->mysqlRealEscapeString( $s );
 570                 }
 571
 572                 return $sQuoted;
 573         }
 574
 575         /**
 576          * MySQL uses `backticks` for identifier quoting instead of the sql standard "double quotes".
 577          *
 578          * @param string $s
 579          * @return string
 580          */
 581         public function addIdentifierQuotes( $s ) {
 582                 // Characters in the range \u0001-\uFFFF are valid in a quoted identifier
 583                 // Remove NUL bytes and escape backticks by doubling
 584                 return '`' . str_replace( array( "\0", '`' ), array( '', '``' ), $s ) . '`';
 585         }
 586
 587         /**
 588          * @param string $name
 589          * @return bool
 590          */
 591         public function isQuotedIdentifier( $name ) {
 592                 return strlen( $name ) && $name[0] == '`' && substr( $name, -1, 1 ) == '`';
 593         }
 594
 595         /**
 596          * @return bool
 597          */
 598         function ping() {
 599                 $ping = $this->mysqlPing();
 600                 if ( $ping ) {
 601                         // Connection was good or lost but reconnected...
 602                         // @note: mysqlnd (php 5.6+) does not support this (PHP bug 52561)
 603                         return true;
 604                 }
 605
 606                 // Try a full disconnect/reconnect cycle if ping() failed
 607                 $this->closeConnection();
 608                 $this->mOpened = false;
 609                 $this->mConn = false;
 610                 $this->open( $this->mServer, $this->mUser, $this->mPassword, $this->mDBname );
 611
 612                 return true;
 613         }
 614
 615         /**
 616          * Ping a server connection or reconnect if there is no connection
 617          *
 618          * @return bool
 619          */
 620         abstract protected function mysqlPing();
 621
 622         /**
 623          * Returns slave lag.
 624          *
 625          * This will do a SHOW SLAVE STATUS
 626          *
 627          * @return int
 628          */
 629         function getLag() {
 630                 if ( $this->lagDetectionMethod === 'pt-heartbeat' ) {
 631                         return $this->getLagFromPtHeartbeat();
 632                 } else {
 633                         return $this->getLagFromSlaveStatus();
 634                 }
 635         }
 636
 637         /**
 638          * @return bool|int
 639          */
 640         protected function getLagFromSlaveStatus() {
 641                 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__ );
 642                 $row = $res ? $res->fetchObject() : false;
 643                 if ( $row && strval( $row->Seconds_Behind_Master ) !== '' ) {
 644                         return intval( $row->Seconds_Behind_Master );
 645                 }
 646
 647                 return false;
 648         }
 649
 650         /**
 651          * @return bool|float
 652          */
 653         protected function getLagFromPtHeartbeat() {
 654                 $key = wfMemcKey( 'mysql', 'master-server-id', $this->getServer() );
 655                 $masterId = intval( $this->srvCache->get( $key ) );
 656                 if ( !$masterId ) {
 657                         $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__ );
 658                         $row = $res ? $res->fetchObject() : false;
 659                         if ( $row && strval( $row->Master_Server_Id ) !== '' ) {
 660                                 $masterId = intval( $row->Master_Server_Id );
 661                                 $this->srvCache->set( $key, $masterId, 30 );
 662                         }
 663                 }
 664
 665                 if ( !$masterId ) {
 666                         return false;
 667                 }
 668
 669                 $res = $this->query(
 670                         "SELECT TIMESTAMPDIFF(MICROSECOND,ts,UTC_TIMESTAMP(6)) AS Lag " .
 671                         "FROM heartbeat.heartbeat WHERE server_id = $masterId"
 672                 );
 673                 $row = $res ? $res->fetchObject() : false;
 674                 if ( $row ) {
 675                         return max( floatval( $row->Lag ) / 1e6, 0.0 );
 676                 }
 677
 678                 return false;
 679         }
 680
 681         /**
 682          * Wait for the slave to catch up to a given master position.
 683          * @todo Return values for this and base class are rubbish
 684          *
 685          * @param DBMasterPos|MySQLMasterPos $pos
 686          * @param int $timeout The maximum number of seconds to wait for synchronisation
 687          * @return int Zero if the slave was past that position already,
 688          *   greater than zero if we waited for some period of time, less than
 689          *   zero if we timed out.
 690          */
 691         function masterPosWait( DBMasterPos $pos, $timeout ) {
 692                 if ( $this->lastKnownSlavePos && $this->lastKnownSlavePos->hasReached( $pos ) ) {
 693                         return '0'; // http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html
 694                 }
 695
 696                 # Commit any open transactions
 697                 $this->commit( __METHOD__, 'flush' );
 698
 699                 # Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
 700                 $encFile = $this->addQuotes( $pos->file );
 701                 $encPos = intval( $pos->pos );
 702                 $sql = "SELECT MASTER_POS_WAIT($encFile, $encPos, $timeout)";
 703                 $res = $this->doQuery( $sql );
 704
 705                 $status = false;
 706                 if ( $res && $row = $this->fetchRow( $res ) ) {
 707                         $status = $row[0]; // can be NULL, -1, or 0+ per the MySQL manual
 708                         if ( ctype_digit( $status ) ) { // success
 709                                 $this->lastKnownSlavePos = $pos;
 710                         }
 711                 }
 712
 713                 return $status;
 714         }
 715
 716         /**
 717          * Get the position of the master from SHOW SLAVE STATUS
 718          *
 719          * @return MySQLMasterPos|bool
 720          */
 721         function getSlavePos() {
 722                 $res = $this->query( 'SHOW SLAVE STATUS', 'DatabaseBase::getSlavePos' );
 723                 $row = $this->fetchObject( $res );
 724
 725                 if ( $row ) {
 726                         $pos = isset( $row->Exec_master_log_pos )
 727                                 ? $row->Exec_master_log_pos
 728                                 : $row->Exec_Master_Log_Pos;
 729
 730                         return new MySQLMasterPos( $row->Relay_Master_Log_File, $pos );
 731                 } else {
 732                         return false;
 733                 }
 734         }
 735
 736         /**
 737          * Get the position of the master from SHOW MASTER STATUS
 738          *
 739          * @return MySQLMasterPos|bool
 740          */
 741         function getMasterPos() {
 742                 $res = $this->query( 'SHOW MASTER STATUS', 'DatabaseBase::getMasterPos' );
 743                 $row = $this->fetchObject( $res );
 744
 745                 if ( $row ) {
 746                         return new MySQLMasterPos( $row->File, $row->Position );
 747                 } else {
 748                         return false;
 749                 }
 750         }
 751
 752         /**
 753          * @param string $index
 754          * @return string
 755          */
 756         function useIndexClause( $index ) {
 757                 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
 758         }
 759
 760         /**
 761          * @return string
 762          */
 763         function lowPriorityOption() {
 764                 return 'LOW_PRIORITY';
 765         }
 766
 767         /**
 768          * @return string
 769          */
 770         public function getSoftwareLink() {
 771                 // MariaDB includes its name in its version string; this is how MariaDB's version of
 772                 // the mysql command-line client identifies MariaDB servers (see mariadb_connection()
 773                 // in libmysql/libmysql.c).
 774                 $version = $this->getServerVersion();
 775                 if ( strpos( $version, 'MariaDB' ) !== false || strpos( $version, '-maria-' ) !== false ) {
 776                         return '[{{int:version-db-mariadb-url}} MariaDB]';
 777                 }
 778
 779                 // Percona Server's version suffix is not very distinctive, and @@version_comment
 780                 // doesn't give the necessary info for source builds, so assume the server is MySQL.
 781                 // (Even Percona's version of mysql doesn't try to make the distinction.)
 782                 return '[{{int:version-db-mysql-url}} MySQL]';
 783         }
 784
 785         /**
 786          * @return string
 787          */
 788         public function getServerVersion() {
 789                 // Not using mysql_get_server_info() or similar for consistency: in the handshake,
 790                 // MariaDB 10 adds the prefix "5.5.5-", and only some newer client libraries strip
 791                 // it off (see RPL_VERSION_HACK in include/mysql_com.h).
 792                 if ( $this->serverVersion === null ) {
 793                         $this->serverVersion = $this->selectField( '', 'VERSION()', '', __METHOD__ );
 794                 }
 795                 return $this->serverVersion;
 796         }
 797
 798         /**
 799          * @param array $options
 800          */
 801         public function setSessionOptions( array $options ) {
 802                 if ( isset( $options['connTimeout'] ) ) {
 803                         $timeout = (int)$options['connTimeout'];
 804                         $this->query( "SET net_read_timeout=$timeout" );
 805                         $this->query( "SET net_write_timeout=$timeout" );
 806                 }
 807         }
 808
 809         /**
 810          * @param string $sql
 811          * @param string $newLine
 812          * @return bool
 813          */
 814         public function streamStatementEnd( &$sql, &$newLine ) {
 815                 if ( strtoupper( substr( $newLine, 0, 9 ) ) == 'DELIMITER' ) {
 816                         preg_match( '/^DELIMITER\s+(\S+)/', $newLine, $m );
 817                         $this->delimiter = $m[1];
 818                         $newLine = '';
 819                 }
 820
 821                 return parent::streamStatementEnd( $sql, $newLine );
 822         }
 823
 824         /**
 825          * Check to see if a named lock is available. This is non-blocking.
 826          *
 827          * @param string $lockName Name of lock to poll
 828          * @param string $method Name of method calling us
 829          * @return bool
 830          * @since 1.20
 831          */
 832         public function lockIsFree( $lockName, $method ) {
 833                 $lockName = $this->addQuotes( $lockName );
 834                 $result = $this->query( "SELECT IS_FREE_LOCK($lockName) AS lockstatus", $method );
 835                 $row = $this->fetchObject( $result );
 836
 837                 return ( $row->lockstatus == 1 );
 838         }
 839
 840         /**
 841          * @param string $lockName
 842          * @param string $method
 843          * @param int $timeout
 844          * @return bool
 845          */
 846         public function lock( $lockName, $method, $timeout = 5 ) {
 847                 $lockName = $this->addQuotes( $lockName );
 848                 $result = $this->query( "SELECT GET_LOCK($lockName, $timeout) AS lockstatus", $method );
 849                 $row = $this->fetchObject( $result );
 850
 851                 if ( $row->lockstatus == 1 ) {
 852                         return true;
 853                 } else {
 854                         wfDebug( __METHOD__ . " failed to acquire lock\n" );
 855
 856                         return false;
 857                 }
 858         }
 859
 860         /**
 861          * FROM MYSQL DOCS:
 862          * http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
 863          * @param string $lockName
 864          * @param string $method
 865          * @return bool
 866          */
 867         public function unlock( $lockName, $method ) {
 868                 $lockName = $this->addQuotes( $lockName );
 869                 $result = $this->query( "SELECT RELEASE_LOCK($lockName) as lockstatus", $method );
 870                 $row = $this->fetchObject( $result );
 871
 872                 return ( $row->lockstatus == 1 );
 873         }
 874
 875         public function namedLocksEnqueue() {
 876                 return true;
 877         }
 878
 879         /**
 880          * @param array $read
 881          * @param array $write
 882          * @param string $method
 883          * @param bool $lowPriority
 884          * @return bool
 885          */
 886         public function lockTables( $read, $write, $method, $lowPriority = true ) {
 887                 $items = array();
 888
 889                 foreach ( $write as $table ) {
 890                         $tbl = $this->tableName( $table ) .
 891                                 ( $lowPriority ? ' LOW_PRIORITY' : '' ) .
 892                                 ' WRITE';
 893                         $items[] = $tbl;
 894                 }
 895                 foreach ( $read as $table ) {
 896                         $items[] = $this->tableName( $table ) . ' READ';
 897                 }
 898                 $sql = "LOCK TABLES " . implode( ',', $items );
 899                 $this->query( $sql, $method );
 900
 901                 return true;
 902         }
 903
 904         /**
 905          * @param string $method
 906          * @return bool
 907          */
 908         public function unlockTables( $method ) {
 909                 $this->query( "UNLOCK TABLES", $method );
 910
 911                 return true;
 912         }
 913
 914         /**
 915          * Get search engine class. All subclasses of this
 916          * need to implement this if they wish to use searching.
 917          *
 918          * @return string
 919          */
 920         public function getSearchEngine() {
 921                 return 'SearchMySQL';
 922         }
 923
 924         /**
 925          * @param bool $value
 926          */
 927         public function setBigSelects( $value = true ) {
 928                 if ( $value === 'default' ) {
 929                         if ( $this->mDefaultBigSelects === null ) {
 930                                 # Function hasn't been called before so it must already be set to the default
 931                                 return;
 932                         } else {
 933                                 $value = $this->mDefaultBigSelects;
 934                         }
 935                 } elseif ( $this->mDefaultBigSelects === null ) {
 936                         $this->mDefaultBigSelects =
 937                                 (bool)$this->selectField( false, '@@sql_big_selects', '', __METHOD__ );
 938                 }
 939                 $encValue = $value ? '1' : '0';
 940                 $this->query( "SET sql_big_selects=$encValue", __METHOD__ );
 941         }
 942
 943         /**
 944          * DELETE where the condition is a join. MySql uses multi-table deletes.
 945          * @param string $delTable
 946          * @param string $joinTable
 947          * @param string $delVar
 948          * @param string $joinVar
 949          * @param array|string $conds
 950          * @param bool|string $fname
 951          * @throws DBUnexpectedError
 952          * @return bool|ResultWrapper
 953          */
 954         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = __METHOD__ ) {
 955                 if ( !$conds ) {
 956                         throw new DBUnexpectedError( $this, 'DatabaseBase::deleteJoin() called with empty $conds' );
 957                 }
 958
 959                 $delTable = $this->tableName( $delTable );
 960                 $joinTable = $this->tableName( $joinTable );
 961                 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
 962
 963                 if ( $conds != '*' ) {
 964                         $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
 965                 }
 966
 967                 return $this->query( $sql, $fname );
 968         }
 969
 970         /**
 971          * @param string $table
 972          * @param array $rows
 973          * @param array $uniqueIndexes
 974          * @param array $set
 975          * @param string $fname
 976          * @return bool
 977          */
 978         public function upsert( $table, array $rows, array $uniqueIndexes,
 979                 array $set, $fname = __METHOD__
 980         ) {
 981                 if ( !count( $rows ) ) {
 982                         return true; // nothing to do
 983                 }
 984
 985                 if ( !is_array( reset( $rows ) ) ) {
 986                         $rows = array( $rows );
 987                 }
 988
 989                 $table = $this->tableName( $table );
 990                 $columns = array_keys( $rows[0] );
 991
 992                 $sql = "INSERT INTO $table (" . implode( ',', $columns ) . ') VALUES ';
 993                 $rowTuples = array();
 994                 foreach ( $rows as $row ) {
 995                         $rowTuples[] = '(' . $this->makeList( $row ) . ')';
 996                 }
 997                 $sql .= implode( ',', $rowTuples );
 998                 $sql .= " ON DUPLICATE KEY UPDATE " . $this->makeList( $set, LIST_SET );
 999
1000                 return (bool)$this->query( $sql, $fname );
1001         }
1002
1003         /**
1004          * Determines how long the server has been up
1005          *
1006          * @return int
1007          */
1008         function getServerUptime() {
1009                 $vars = $this->getMysqlStatus( 'Uptime' );
1010
1011                 return (int)$vars['Uptime'];
1012         }
1013
1014         /**
1015          * Determines if the last failure was due to a deadlock
1016          *
1017          * @return bool
1018          */
1019         function wasDeadlock() {
1020                 return $this->lastErrno() == 1213;
1021         }
1022
1023         /**
1024          * Determines if the last failure was due to a lock timeout
1025          *
1026          * @return bool
1027          */
1028         function wasLockTimeout() {
1029                 return $this->lastErrno() == 1205;
1030         }
1031
1032         /**
1033          * Determines if the last query error was something that should be dealt
1034          * with by pinging the connection and reissuing the query
1035          *
1036          * @return bool
1037          */
1038         function wasErrorReissuable() {
1039                 return $this->lastErrno() == 2013 || $this->lastErrno() == 2006;
1040         }
1041
1042         /**
1043          * Determines if the last failure was due to the database being read-only.
1044          *
1045          * @return bool
1046          */
1047         function wasReadOnlyError() {
1048                 return $this->lastErrno() == 1223 ||
1049                         ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
1050         }
1051
1052         function wasConnectionError( $errno ) {
1053                 return $errno == 2013 || $errno == 2006;
1054         }
1055
1056         /**
1057          * Get the underlying binding handle, mConn
1058          *
1059          * Makes sure that mConn is set (disconnects and ping() failure can unset it).
1060          * This catches broken callers than catch and ignore disconnection exceptions.
1061          * Unlike checking isOpen(), this is safe to call inside of open().
1062          *
1063          * @return resource|object
1064          * @throws DBUnexpectedError
1065          * @since 1.26
1066          */
1067         protected function getBindingHandle() {
1068                 if ( !$this->mConn ) {
1069                         throw new DBUnexpectedError(
1070                                 $this,
1071                                 'DB connection was already closed or the connection dropped.'
1072                         );
1073                 }
1074
1075                 return $this->mConn;
1076         }
1077
1078         /**
1079          * @param string $oldName
1080          * @param string $newName
1081          * @param bool $temporary
1082          * @param string $fname
1083          * @return bool
1084          */
1085         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
1086                 $tmp = $temporary ? 'TEMPORARY ' : '';
1087                 $newName = $this->addIdentifierQuotes( $newName );
1088                 $oldName = $this->addIdentifierQuotes( $oldName );
1089                 $query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
1090
1091                 return $this->query( $query, $fname );
1092         }
1093
1094         /**
1095          * List all tables on the database
1096          *
1097          * @param string $prefix Only show tables with this prefix, e.g. mw_
1098          * @param string $fname Calling function name
1099          * @return array
1100          */
1101         function listTables( $prefix = null, $fname = __METHOD__ ) {
1102                 $result = $this->query( "SHOW TABLES", $fname );
1103
1104                 $endArray = array();
1105
1106                 foreach ( $result as $table ) {
1107                         $vars = get_object_vars( $table );
1108                         $table = array_pop( $vars );
1109
1110                         if ( !$prefix || strpos( $table, $prefix ) === 0 ) {
1111                                 $endArray[] = $table;
1112                         }
1113                 }
1114
1115                 return $endArray;
1116         }
1117
1118         /**
1119          * @param string $tableName
1120          * @param string $fName
1121          * @return bool|ResultWrapper
1122          */
1123         public function dropTable( $tableName, $fName = __METHOD__ ) {
1124                 if ( !$this->tableExists( $tableName, $fName ) ) {
1125                         return false;
1126                 }
1127
1128                 return $this->query( "DROP TABLE IF EXISTS " . $this->tableName( $tableName ), $fName );
1129         }
1130
1131         /**
1132          * @return array
1133          */
1134         protected function getDefaultSchemaVars() {
1135                 $vars = parent::getDefaultSchemaVars();
1136                 $vars['wgDBTableOptions'] = str_replace( 'TYPE', 'ENGINE', $GLOBALS['wgDBTableOptions'] );
1137                 $vars['wgDBTableOptions'] = str_replace(
1138                         'CHARSET=mysql4',
1139                         'CHARSET=binary',
1140                         $vars['wgDBTableOptions']
1141                 );
1142
1143                 return $vars;
1144         }
1145
1146         /**
1147          * Get status information from SHOW STATUS in an associative array
1148          *
1149          * @param string $which
1150          * @return array
1151          */
1152         function getMysqlStatus( $which = "%" ) {
1153                 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
1154                 $status = array();
1155
1156                 foreach ( $res as $row ) {
1157                         $status[$row->Variable_name] = $row->Value;
1158                 }
1159
1160                 return $status;
1161         }
1162
1163         /**
1164          * Lists VIEWs in the database
1165          *
1166          * @param string $prefix Only show VIEWs with this prefix, eg.
1167          * unit_test_, or $wgDBprefix. Default: null, would return all views.
1168          * @param string $fname Name of calling function
1169          * @return array
1170          * @since 1.22
1171          */
1172         public function listViews( $prefix = null, $fname = __METHOD__ ) {
1173
1174                 if ( !isset( $this->allViews ) ) {
1175
1176                         // The name of the column containing the name of the VIEW
1177                         $propertyName = 'Tables_in_' . $this->mDBname;
1178
1179                         // Query for the VIEWS
1180                         $result = $this->query( 'SHOW FULL TABLES WHERE TABLE_TYPE = "VIEW"' );
1181                         $this->allViews = array();
1182                         while ( ( $row = $this->fetchRow( $result ) ) !== false ) {
1183                                 array_push( $this->allViews, $row[$propertyName] );
1184                         }
1185                 }
1186
1187                 if ( is_null( $prefix ) || $prefix === '' ) {
1188                         return $this->allViews;
1189                 }
1190
1191                 $filteredViews = array();
1192                 foreach ( $this->allViews as $viewName ) {
1193                         // Does the name of this VIEW start with the table-prefix?
1194                         if ( strpos( $viewName, $prefix ) === 0 ) {
1195                                 array_push( $filteredViews, $viewName );
1196                         }
1197                 }
1198
1199                 return $filteredViews;
1200         }
1201
1202         /**
1203          * Differentiates between a TABLE and a VIEW.
1204          *
1205          * @param string $name Name of the TABLE/VIEW to test
1206          * @param string $prefix
1207          * @return bool
1208          * @since 1.22
1209          */
1210         public function isView( $name, $prefix = null ) {
1211                 return in_array( $name, $this->listViews( $prefix ) );
1212         }
1213 }
1214
1215 /**
1216  * Utility class.
1217  * @ingroup Database
1218  */
1219 class MySQLField implements Field {
1220         private $name, $tablename, $default, $max_length, $nullable,
1221                 $is_pk, $is_unique, $is_multiple, $is_key, $type, $binary,
1222                 $is_numeric, $is_blob, $is_unsigned, $is_zerofill;
1223
1224         function __construct( $info ) {
1225                 $this->name = $info->name;
1226                 $this->tablename = $info->table;
1227                 $this->default = $info->def;
1228                 $this->max_length = $info->max_length;
1229                 $this->nullable = !$info->not_null;
1230                 $this->is_pk = $info->primary_key;
1231                 $this->is_unique = $info->unique_key;
1232                 $this->is_multiple = $info->multiple_key;
1233                 $this->is_key = ( $this->is_pk || $this->is_unique || $this->is_multiple );
1234                 $this->type = $info->type;
1235                 $this->binary = isset( $info->binary ) ? $info->binary : false;
1236                 $this->is_numeric = isset( $info->numeric ) ? $info->numeric : false;
1237                 $this->is_blob = isset( $info->blob ) ? $info->blob : false;
1238                 $this->is_unsigned = isset( $info->unsigned ) ? $info->unsigned : false;
1239                 $this->is_zerofill = isset( $info->zerofill ) ? $info->zerofill : false;
1240         }
1241
1242         /**
1243          * @return string
1244          */
1245         function name() {
1246                 return $this->name;
1247         }
1248
1249         /**
1250          * @return string
1251          */
1252         function tableName() {
1253                 return $this->tableName;
1254         }
1255
1256         /**
1257          * @return string
1258          */
1259         function type() {
1260                 return $this->type;
1261         }
1262
1263         /**
1264          * @return bool
1265          */
1266         function isNullable() {
1267                 return $this->nullable;
1268         }
1269
1270         function defaultValue() {
1271                 return $this->default;
1272         }
1273
1274         /**
1275          * @return bool
1276          */
1277         function isKey() {
1278                 return $this->is_key;
1279         }
1280
1281         /**
1282          * @return bool
1283          */
1284         function isMultipleKey() {
1285                 return $this->is_multiple;
1286         }
1287
1288         /**
1289          * @return bool
1290          */
1291         function isBinary() {
1292                 return $this->binary;
1293         }
1294
1295         /**
1296          * @return bool
1297          */
1298         function isNumeric() {
1299                 return $this->is_numeric;
1300         }
1301
1302         /**
1303          * @return bool
1304          */
1305         function isBlob() {
1306                 return $this->is_blob;
1307         }
1308
1309         /**
1310          * @return bool
1311          */
1312         function isUnsigned() {
1313                 return $this->is_unsigned;
1314         }
1315
1316         /**
1317          * @return bool
1318          */
1319         function isZerofill() {
1320                 return $this->is_zerofill;
1321         }
1322 }
1323
1324 class MySQLMasterPos implements DBMasterPos {
1325         /** @var string */
1326         public $file;
1327         /** @var int Position */
1328         public $pos;
1329         /** @var float UNIX timestamp */
1330         public $asOfTime = 0.0;
1331
1332         function __construct( $file, $pos ) {
1333                 $this->file = $file;
1334                 $this->pos = $pos;
1335                 $this->asOfTime = microtime( true );
1336         }
1337
1338         function __toString() {
1339                 // e.g db1034-bin.000976/843431247
1340                 return "{$this->file}/{$this->pos}";
1341         }
1342
1343         /**
1344          * @return array|bool (int, int)
1345          */
1346         protected function getCoordinates() {
1347                 $m = array();
1348                 if ( preg_match( '!\.(\d+)/(\d+)$!', (string)$this, $m ) ) {
1349                         return array( (int)$m[1], (int)$m[2] );
1350                 }
1351
1352                 return false;
1353         }
1354
1355         function hasReached( MySQLMasterPos $pos ) {
1356                 $thisPos = $this->getCoordinates();
1357                 $thatPos = $pos->getCoordinates();
1358
1359                 return ( $thisPos && $thatPos && $thisPos >= $thatPos );
1360         }
1361
1362         function asOfTime() {
1363                 return $this->asOfTime;
1364         }
1365 }