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 Database {
  33         /** @var MysqlMasterPos */
  34         protected $lastKnownReplicaPos;
  35         /** @var string Method to detect replica DB lag */
  36         protected $lagDetectionMethod;
  37         /** @var array Method to detect replica DB lag */
  38         protected $lagDetectionOptions = [];
  39         /** @var bool bool Whether to use GTID methods */
  40         protected $useGTIDs = false;
  41         /** @var string|null */
  42         protected $sslKeyPath;
  43         /** @var string|null */
  44         protected $sslCertPath;
  45         /** @var string|null */
  46         protected $sslCAPath;
  47         /** @var string[]|null */
  48         protected $sslCiphers;
  49         /** @var string|null */
  50         private $serverVersion = null;
  51
  52         /**
  53          * Additional $params include:
  54          *   - lagDetectionMethod : set to one of (Seconds_Behind_Master,pt-heartbeat).
  55          *       pt-heartbeat assumes the table is at heartbeat.heartbeat
  56          *       and uses UTC timestamps in the heartbeat.ts column.
  57          *       (https://www.percona.com/doc/percona-toolkit/2.2/pt-heartbeat.html)
  58          *   - lagDetectionOptions : if using pt-heartbeat, this can be set to an array map to change
  59          *       the default behavior. Normally, the heartbeat row with the server
  60          *       ID of this server's master will be used. Set the "conds" field to
  61          *       override the query conditions, e.g. ['shard' => 's1'].
  62          *   - useGTIDs : use GTID methods like MASTER_GTID_WAIT() when possible.
  63          *   - sslKeyPath : path to key file [default: null]
  64          *   - sslCertPath : path to certificate file [default: null]
  65          *   - sslCAPath : parth to certificate authority PEM files [default: null]
  66          *   - sslCiphers : array list of allowable ciphers [default: null]
  67          * @param array $params
  68          */
  69         function __construct( array $params ) {
  70                 parent::__construct( $params );
  71
  72                 $this->lagDetectionMethod = isset( $params['lagDetectionMethod'] )
  73                         ? $params['lagDetectionMethod']
  74                         : 'Seconds_Behind_Master';
  75                 $this->lagDetectionOptions = isset( $params['lagDetectionOptions'] )
  76                         ? $params['lagDetectionOptions']
  77                         : [];
  78                 $this->useGTIDs = !empty( $params['useGTIDs' ] );
  79                 foreach ( [ 'KeyPath', 'CertPath', 'CAPath', 'Ciphers' ] as $name ) {
  80                         $var = "ssl{$name}";
  81                         if ( isset( $params[$var] ) ) {
  82                                 $this->$var = $params[$var];
  83                         }
  84                 }
  85         }
  86
  87         /**
  88          * @return string
  89          */
  90         function getType() {
  91                 return 'mysql';
  92         }
  93
  94         /**
  95          * @param string $server
  96          * @param string $user
  97          * @param string $password
  98          * @param string $dbName
  99          * @throws Exception|DBConnectionError
 100          * @return bool
 101          */
 102         function open( $server, $user, $password, $dbName ) {
 103                 global $wgAllDBsAreLocalhost, $wgSQLMode;
 104
 105                 # Close/unset connection handle
 106                 $this->close();
 107
 108                 # Debugging hack -- fake cluster
 109                 $realServer = $wgAllDBsAreLocalhost ? 'localhost' : $server;
 110                 $this->mServer = $server;
 111                 $this->mUser = $user;
 112                 $this->mPassword = $password;
 113                 $this->mDBname = $dbName;
 114
 115                 $this->installErrorHandler();
 116                 try {
 117                         $this->mConn = $this->mysqlConnect( $realServer );
 118                 } catch ( Exception $ex ) {
 119                         $this->restoreErrorHandler();
 120                         throw $ex;
 121                 }
 122                 $error = $this->restoreErrorHandler();
 123
 124                 # Always log connection errors
 125                 if ( !$this->mConn ) {
 126                         if ( !$error ) {
 127                                 $error = $this->lastError();
 128                         }
 129                         wfLogDBError(
 130                                 "Error connecting to {db_server}: {error}",
 131                                 $this->getLogContext( [
 132                                         'method' => __METHOD__,
 133                                         'error' => $error,
 134                                 ] )
 135                         );
 136                         wfDebug( "DB connection error\n" .
 137                                 "Server: $server, User: $user, Password: " .
 138                                 substr( $password, 0, 3 ) . "..., error: " . $error . "\n" );
 139
 140                         $this->reportConnectionError( $error );
 141                 }
 142
 143                 if ( $dbName != '' ) {
 144                         MediaWiki\suppressWarnings();
 145                         $success = $this->selectDB( $dbName );
 146                         MediaWiki\restoreWarnings();
 147                         if ( !$success ) {
 148                                 wfLogDBError(
 149                                         "Error selecting database {db_name} on server {db_server}",
 150                                         $this->getLogContext( [
 151                                                 'method' => __METHOD__,
 152                                         ] )
 153                                 );
 154                                 wfDebug( "Error selecting database $dbName on server {$this->mServer} " .
 155                                         "from client host " . wfHostname() . "\n" );
 156
 157                                 $this->reportConnectionError( "Error selecting database $dbName" );
 158                         }
 159                 }
 160
 161                 // Tell the server what we're communicating with
 162                 if ( !$this->connectInitCharset() ) {
 163                         $this->reportConnectionError( "Error setting character set" );
 164                 }
 165
 166                 // Abstract over any insane MySQL defaults
 167                 $set = [ 'group_concat_max_len = 262144' ];
 168                 // Set SQL mode, default is turning them all off, can be overridden or skipped with null
 169                 if ( is_string( $wgSQLMode ) ) {
 170                         $set[] = 'sql_mode = ' . $this->addQuotes( $wgSQLMode );
 171                 }
 172                 // Set any custom settings defined by site config
 173                 // (e.g. https://dev.mysql.com/doc/refman/4.1/en/innodb-parameters.html)
 174                 foreach ( $this->mSessionVars as $var => $val ) {
 175                         // Escape strings but not numbers to avoid MySQL complaining
 176                         if ( !is_int( $val ) && !is_float( $val ) ) {
 177                                 $val = $this->addQuotes( $val );
 178                         }
 179                         $set[] = $this->addIdentifierQuotes( $var ) . ' = ' . $val;
 180                 }
 181
 182                 if ( $set ) {
 183                         // Use doQuery() to avoid opening implicit transactions (DBO_TRX)
 184                         $success = $this->doQuery( 'SET ' . implode( ', ', $set ) );
 185                         if ( !$success ) {
 186                                 wfLogDBError(
 187                                         'Error setting MySQL variables on server {db_server} (check $wgSQLMode)',
 188                                         $this->getLogContext( [
 189                                                 'method' => __METHOD__,
 190                                         ] )
 191                                 );
 192                                 $this->reportConnectionError(
 193                                         'Error setting MySQL variables on server {db_server} (check $wgSQLMode)' );
 194                         }
 195                 }
 196
 197                 $this->mOpened = true;
 198
 199                 return true;
 200         }
 201
 202         /**
 203          * Set the character set information right after connection
 204          * @return bool
 205          */
 206         protected function connectInitCharset() {
 207                 global $wgDBmysql5;
 208
 209                 if ( $wgDBmysql5 ) {
 210                         // Tell the server we're communicating with it in UTF-8.
 211                         // This may engage various charset conversions.
 212                         return $this->mysqlSetCharset( 'utf8' );
 213                 } else {
 214                         return $this->mysqlSetCharset( 'binary' );
 215                 }
 216         }
 217
 218         /**
 219          * Open a connection to a MySQL server
 220          *
 221          * @param string $realServer
 222          * @return mixed Raw connection
 223          * @throws DBConnectionError
 224          */
 225         abstract protected function mysqlConnect( $realServer );
 226
 227         /**
 228          * Set the character set of the MySQL link
 229          *
 230          * @param string $charset
 231          * @return bool
 232          */
 233         abstract protected function mysqlSetCharset( $charset );
 234
 235         /**
 236          * @param ResultWrapper|resource $res
 237          * @throws DBUnexpectedError
 238          */
 239         function freeResult( $res ) {
 240                 if ( $res instanceof ResultWrapper ) {
 241                         $res = $res->result;
 242                 }
 243                 MediaWiki\suppressWarnings();
 244                 $ok = $this->mysqlFreeResult( $res );
 245                 MediaWiki\restoreWarnings();
 246                 if ( !$ok ) {
 247                         throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
 248                 }
 249         }
 250
 251         /**
 252          * Free result memory
 253          *
 254          * @param resource $res Raw result
 255          * @return bool
 256          */
 257         abstract protected function mysqlFreeResult( $res );
 258
 259         /**
 260          * @param ResultWrapper|resource $res
 261          * @return stdClass|bool
 262          * @throws DBUnexpectedError
 263          */
 264         function fetchObject( $res ) {
 265                 if ( $res instanceof ResultWrapper ) {
 266                         $res = $res->result;
 267                 }
 268                 MediaWiki\suppressWarnings();
 269                 $row = $this->mysqlFetchObject( $res );
 270                 MediaWiki\restoreWarnings();
 271
 272                 $errno = $this->lastErrno();
 273                 // Unfortunately, mysql_fetch_object does not reset the last errno.
 274                 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
 275                 // these are the only errors mysql_fetch_object can cause.
 276                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 277                 if ( $errno == 2000 || $errno == 2013 ) {
 278                         throw new DBUnexpectedError(
 279                                 $this,
 280                                 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() )
 281                         );
 282                 }
 283
 284                 return $row;
 285         }
 286
 287         /**
 288          * Fetch a result row as an object
 289          *
 290          * @param resource $res Raw result
 291          * @return stdClass
 292          */
 293         abstract protected function mysqlFetchObject( $res );
 294
 295         /**
 296          * @param ResultWrapper|resource $res
 297          * @return array|bool
 298          * @throws DBUnexpectedError
 299          */
 300         function fetchRow( $res ) {
 301                 if ( $res instanceof ResultWrapper ) {
 302                         $res = $res->result;
 303                 }
 304                 MediaWiki\suppressWarnings();
 305                 $row = $this->mysqlFetchArray( $res );
 306                 MediaWiki\restoreWarnings();
 307
 308                 $errno = $this->lastErrno();
 309                 // Unfortunately, mysql_fetch_array does not reset the last errno.
 310                 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
 311                 // these are the only errors mysql_fetch_array can cause.
 312                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 313                 if ( $errno == 2000 || $errno == 2013 ) {
 314                         throw new DBUnexpectedError(
 315                                 $this,
 316                                 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() )
 317                         );
 318                 }
 319
 320                 return $row;
 321         }
 322
 323         /**
 324          * Fetch a result row as an associative and numeric array
 325          *
 326          * @param resource $res Raw result
 327          * @return array
 328          */
 329         abstract protected function mysqlFetchArray( $res );
 330
 331         /**
 332          * @throws DBUnexpectedError
 333          * @param ResultWrapper|resource $res
 334          * @return int
 335          */
 336         function numRows( $res ) {
 337                 if ( $res instanceof ResultWrapper ) {
 338                         $res = $res->result;
 339                 }
 340                 MediaWiki\suppressWarnings();
 341                 $n = $this->mysqlNumRows( $res );
 342                 MediaWiki\restoreWarnings();
 343
 344                 // Unfortunately, mysql_num_rows does not reset the last errno.
 345                 // We are not checking for any errors here, since
 346                 // these are no errors mysql_num_rows can cause.
 347                 // See http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
 348                 // See https://phabricator.wikimedia.org/T44430
 349                 return $n;
 350         }
 351
 352         /**
 353          * Get number of rows in result
 354          *
 355          * @param resource $res Raw result
 356          * @return int
 357          */
 358         abstract protected function mysqlNumRows( $res );
 359
 360         /**
 361          * @param ResultWrapper|resource $res
 362          * @return int
 363          */
 364         function numFields( $res ) {
 365                 if ( $res instanceof ResultWrapper ) {
 366                         $res = $res->result;
 367                 }
 368
 369                 return $this->mysqlNumFields( $res );
 370         }
 371
 372         /**
 373          * Get number of fields in result
 374          *
 375          * @param resource $res Raw result
 376          * @return int
 377          */
 378         abstract protected function mysqlNumFields( $res );
 379
 380         /**
 381          * @param ResultWrapper|resource $res
 382          * @param int $n
 383          * @return string
 384          */
 385         function fieldName( $res, $n ) {
 386                 if ( $res instanceof ResultWrapper ) {
 387                         $res = $res->result;
 388                 }
 389
 390                 return $this->mysqlFieldName( $res, $n );
 391         }
 392
 393         /**
 394          * Get the name of the specified field in a result
 395          *
 396          * @param ResultWrapper|resource $res
 397          * @param int $n
 398          * @return string
 399          */
 400         abstract protected function mysqlFieldName( $res, $n );
 401
 402         /**
 403          * mysql_field_type() wrapper
 404          * @param ResultWrapper|resource $res
 405          * @param int $n
 406          * @return string
 407          */
 408         public function fieldType( $res, $n ) {
 409                 if ( $res instanceof ResultWrapper ) {
 410                         $res = $res->result;
 411                 }
 412
 413                 return $this->mysqlFieldType( $res, $n );
 414         }
 415
 416         /**
 417          * Get the type of the specified field in a result
 418          *
 419          * @param ResultWrapper|resource $res
 420          * @param int $n
 421          * @return string
 422          */
 423         abstract protected function mysqlFieldType( $res, $n );
 424
 425         /**
 426          * @param ResultWrapper|resource $res
 427          * @param int $row
 428          * @return bool
 429          */
 430         function dataSeek( $res, $row ) {
 431                 if ( $res instanceof ResultWrapper ) {
 432                         $res = $res->result;
 433                 }
 434
 435                 return $this->mysqlDataSeek( $res, $row );
 436         }
 437
 438         /**
 439          * Move internal result pointer
 440          *
 441          * @param ResultWrapper|resource $res
 442          * @param int $row
 443          * @return bool
 444          */
 445         abstract protected function mysqlDataSeek( $res, $row );
 446
 447         /**
 448          * @return string
 449          */
 450         function lastError() {
 451                 if ( $this->mConn ) {
 452                         # Even if it's non-zero, it can still be invalid
 453                         MediaWiki\suppressWarnings();
 454                         $error = $this->mysqlError( $this->mConn );
 455                         if ( !$error ) {
 456                                 $error = $this->mysqlError();
 457                         }
 458                         MediaWiki\restoreWarnings();
 459                 } else {
 460                         $error = $this->mysqlError();
 461                 }
 462                 if ( $error ) {
 463                         $error .= ' (' . $this->mServer . ')';
 464                 }
 465
 466                 return $error;
 467         }
 468
 469         /**
 470          * Returns the text of the error message from previous MySQL operation
 471          *
 472          * @param resource $conn Raw connection
 473          * @return string
 474          */
 475         abstract protected function mysqlError( $conn = null );
 476
 477         /**
 478          * @param string $table
 479          * @param array $uniqueIndexes
 480          * @param array $rows
 481          * @param string $fname
 482          * @return ResultWrapper
 483          */
 484         function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__ ) {
 485                 return $this->nativeReplace( $table, $rows, $fname );
 486         }
 487
 488         /**
 489          * Estimate rows in dataset
 490          * Returns estimated count, based on EXPLAIN output
 491          * Takes same arguments as Database::select()
 492          *
 493          * @param string|array $table
 494          * @param string|array $vars
 495          * @param string|array $conds
 496          * @param string $fname
 497          * @param string|array $options
 498          * @return bool|int
 499          */
 500         public function estimateRowCount( $table, $vars = '*', $conds = '',
 501                 $fname = __METHOD__, $options = []
 502         ) {
 503                 $options['EXPLAIN'] = true;
 504                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 505                 if ( $res === false ) {
 506                         return false;
 507                 }
 508                 if ( !$this->numRows( $res ) ) {
 509                         return 0;
 510                 }
 511
 512                 $rows = 1;
 513                 foreach ( $res as $plan ) {
 514                         $rows *= $plan->rows > 0 ? $plan->rows : 1; // avoid resetting to zero
 515                 }
 516
 517                 return (int)$rows;
 518         }
 519
 520         /**
 521          * @param string $table
 522          * @param string $field
 523          * @return bool|MySQLField
 524          */
 525         function fieldInfo( $table, $field ) {
 526                 $table = $this->tableName( $table );
 527                 $res = $this->query( "SELECT * FROM $table LIMIT 1", __METHOD__, true );
 528                 if ( !$res ) {
 529                         return false;
 530                 }
 531                 $n = $this->mysqlNumFields( $res->result );
 532                 for ( $i = 0; $i < $n; $i++ ) {
 533                         $meta = $this->mysqlFetchField( $res->result, $i );
 534                         if ( $field == $meta->name ) {
 535                                 return new MySQLField( $meta );
 536                         }
 537                 }
 538
 539                 return false;
 540         }
 541
 542         /**
 543          * Get column information from a result
 544          *
 545          * @param resource $res Raw result
 546          * @param int $n
 547          * @return stdClass
 548          */
 549         abstract protected function mysqlFetchField( $res, $n );
 550
 551         /**
 552          * Get information about an index into an object
 553          * Returns false if the index does not exist
 554          *
 555          * @param string $table
 556          * @param string $index
 557          * @param string $fname
 558          * @return bool|array|null False or null on failure
 559          */
 560         function indexInfo( $table, $index, $fname = __METHOD__ ) {
 561                 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
 562                 # SHOW INDEX should work for 3.x and up:
 563                 # http://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
 564                 $table = $this->tableName( $table );
 565                 $index = $this->indexName( $index );
 566
 567                 $sql = 'SHOW INDEX FROM ' . $table;
 568                 $res = $this->query( $sql, $fname );
 569
 570                 if ( !$res ) {
 571                         return null;
 572                 }
 573
 574                 $result = [];
 575
 576                 foreach ( $res as $row ) {
 577                         if ( $row->Key_name == $index ) {
 578                                 $result[] = $row;
 579                         }
 580                 }
 581
 582                 return empty( $result ) ? false : $result;
 583         }
 584
 585         /**
 586          * @param string $s
 587          * @return string
 588          */
 589         function strencode( $s ) {
 590                 return $this->mysqlRealEscapeString( $s );
 591         }
 592
 593         /**
 594          * @param string $s
 595          * @return mixed
 596          */
 597         abstract protected function mysqlRealEscapeString( $s );
 598
 599         /**
 600          * MySQL uses `backticks` for identifier quoting instead of the sql standard "double quotes".
 601          *
 602          * @param string $s
 603          * @return string
 604          */
 605         public function addIdentifierQuotes( $s ) {
 606                 // Characters in the range \u0001-\uFFFF are valid in a quoted identifier
 607                 // Remove NUL bytes and escape backticks by doubling
 608                 return '`' . str_replace( [ "\0", '`' ], [ '', '``' ], $s ) . '`';
 609         }
 610
 611         /**
 612          * @param string $name
 613          * @return bool
 614          */
 615         public function isQuotedIdentifier( $name ) {
 616                 return strlen( $name ) && $name[0] == '`' && substr( $name, -1, 1 ) == '`';
 617         }
 618
 619         function getLag() {
 620                 if ( $this->getLagDetectionMethod() === 'pt-heartbeat' ) {
 621                         return $this->getLagFromPtHeartbeat();
 622                 } else {
 623                         return $this->getLagFromSlaveStatus();
 624                 }
 625         }
 626
 627         /**
 628          * @return string
 629          */
 630         protected function getLagDetectionMethod() {
 631                 return $this->lagDetectionMethod;
 632         }
 633
 634         /**
 635          * @return bool|int
 636          */
 637         protected function getLagFromSlaveStatus() {
 638                 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__ );
 639                 $row = $res ? $res->fetchObject() : false;
 640                 if ( $row && strval( $row->Seconds_Behind_Master ) !== '' ) {
 641                         return intval( $row->Seconds_Behind_Master );
 642                 }
 643
 644                 return false;
 645         }
 646
 647         /**
 648          * @return bool|float
 649          */
 650         protected function getLagFromPtHeartbeat() {
 651                 $options = $this->lagDetectionOptions;
 652
 653                 if ( isset( $options['conds'] ) ) {
 654                         // Best method for multi-DC setups: use logical channel names
 655                         $data = $this->getHeartbeatData( $options['conds'] );
 656                 } else {
 657                         // Standard method: use master server ID (works with stock pt-heartbeat)
 658                         $masterInfo = $this->getMasterServerInfo();
 659                         if ( !$masterInfo ) {
 660                                 wfLogDBError(
 661                                         "Unable to query master of {db_server} for server ID",
 662                                         $this->getLogContext( [
 663                                                 'method' => __METHOD__
 664                                         ] )
 665                                 );
 666
 667                                 return false; // could not get master server ID
 668                         }
 669
 670                         $conds = [ 'server_id' => intval( $masterInfo['serverId'] ) ];
 671                         $data = $this->getHeartbeatData( $conds );
 672                 }
 673
 674                 list( $time, $nowUnix ) = $data;
 675                 if ( $time !== null ) {
 676                         // @time is in ISO format like "2015-09-25T16:48:10.000510"
 677                         $dateTime = new DateTime( $time, new DateTimeZone( 'UTC' ) );
 678                         $timeUnix = (int)$dateTime->format( 'U' ) + $dateTime->format( 'u' ) / 1e6;
 679
 680                         return max( $nowUnix - $timeUnix, 0.0 );
 681                 }
 682
 683                 wfLogDBError(
 684                         "Unable to find pt-heartbeat row for {db_server}",
 685                         $this->getLogContext( [
 686                                 'method' => __METHOD__
 687                         ] )
 688                 );
 689
 690                 return false;
 691         }
 692
 693         protected function getMasterServerInfo() {
 694                 $cache = $this->srvCache;
 695                 $key = $cache->makeGlobalKey(
 696                         'mysql',
 697                         'master-info',
 698                         // Using one key for all cluster replica DBs is preferable
 699                         $this->getLBInfo( 'clusterMasterHost' ) ?: $this->getServer()
 700                 );
 701
 702                 return $cache->getWithSetCallback(
 703                         $key,
 704                         $cache::TTL_INDEFINITE,
 705                         function () use ( $cache, $key ) {
 706                                 // Get and leave a lock key in place for a short period
 707                                 if ( !$cache->lock( $key, 0, 10 ) ) {
 708                                         return false; // avoid master connection spike slams
 709                                 }
 710
 711                                 $conn = $this->getLazyMasterHandle();
 712                                 if ( !$conn ) {
 713                                         return false; // something is misconfigured
 714                                 }
 715
 716                                 // Connect to and query the master; catch errors to avoid outages
 717                                 try {
 718                                         $res = $conn->query( 'SELECT @@server_id AS id', __METHOD__ );
 719                                         $row = $res ? $res->fetchObject() : false;
 720                                         $id = $row ? (int)$row->id : 0;
 721                                 } catch ( DBError $e ) {
 722                                         $id = 0;
 723                                 }
 724
 725                                 // Cache the ID if it was retrieved
 726                                 return $id ? [ 'serverId' => $id, 'asOf' => time() ] : false;
 727                         }
 728                 );
 729         }
 730
 731         /**
 732          * @param array $conds WHERE clause conditions to find a row
 733          * @return array (heartbeat `ts` column value or null, UNIX timestamp) for the newest beat
 734          * @see https://www.percona.com/doc/percona-toolkit/2.1/pt-heartbeat.html
 735          */
 736         protected function getHeartbeatData( array $conds ) {
 737                 $whereSQL = $this->makeList( $conds, LIST_AND );
 738                 // Use ORDER BY for channel based queries since that field might not be UNIQUE.
 739                 // Note: this would use "TIMESTAMPDIFF(MICROSECOND,ts,UTC_TIMESTAMP(6))" but the
 740                 // percision field is not supported in MySQL <= 5.5.
 741                 $res = $this->query(
 742                         "SELECT ts FROM heartbeat.heartbeat WHERE $whereSQL ORDER BY ts DESC LIMIT 1"
 743                 );
 744                 $row = $res ? $res->fetchObject() : false;
 745
 746                 return [ $row ? $row->ts : null, microtime( true ) ];
 747         }
 748
 749         public function getApproximateLagStatus() {
 750                 if ( $this->getLagDetectionMethod() === 'pt-heartbeat' ) {
 751                         // Disable caching since this is fast enough and we don't wan't
 752                         // to be *too* pessimistic by having both the cache TTL and the
 753                         // pt-heartbeat interval count as lag in getSessionLagStatus()
 754                         return parent::getApproximateLagStatus();
 755                 }
 756
 757                 $key = $this->srvCache->makeGlobalKey( 'mysql-lag', $this->getServer() );
 758                 $approxLag = $this->srvCache->get( $key );
 759                 if ( !$approxLag ) {
 760                         $approxLag = parent::getApproximateLagStatus();
 761                         $this->srvCache->set( $key, $approxLag, 1 );
 762                 }
 763
 764                 return $approxLag;
 765         }
 766
 767         function masterPosWait( DBMasterPos $pos, $timeout ) {
 768                 if ( !( $pos instanceof MySQLMasterPos ) ) {
 769                         throw new InvalidArgumentException( "Position not an instance of MySQLMasterPos" );
 770                 }
 771
 772                 if ( $this->getLBInfo( 'is static' ) === true ) {
 773                         return 0; // this is a copy of a read-only dataset with no master DB
 774                 } elseif ( $this->lastKnownReplicaPos && $this->lastKnownReplicaPos->hasReached( $pos ) ) {
 775                         return 0; // already reached this point for sure
 776                 }
 777
 778                 // Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
 779                 if ( $this->useGTIDs && $pos->gtids ) {
 780                         // Wait on the GTID set (MariaDB only)
 781                         $gtidArg = $this->addQuotes( implode( ',', $pos->gtids ) );
 782                         $res = $this->doQuery( "SELECT MASTER_GTID_WAIT($gtidArg, $timeout)" );
 783                 } else {
 784                         // Wait on the binlog coordinates
 785                         $encFile = $this->addQuotes( $pos->file );
 786                         $encPos = intval( $pos->pos );
 787                         $res = $this->doQuery( "SELECT MASTER_POS_WAIT($encFile, $encPos, $timeout)" );
 788                 }
 789
 790                 $row = $res ? $this->fetchRow( $res ) : false;
 791                 if ( !$row ) {
 792                         throw new DBExpectedError( $this, "Failed to query MASTER_POS_WAIT()" );
 793                 }
 794
 795                 // Result can be NULL (error), -1 (timeout), or 0+ per the MySQL manual
 796                 $status = ( $row[0] !== null ) ? intval( $row[0] ) : null;
 797                 if ( $status === null ) {
 798                         // T126436: jobs programmed to wait on master positions might be referencing binlogs
 799                         // with an old master hostname. Such calls make MASTER_POS_WAIT() return null. Try
 800                         // to detect this and treat the replica DB as having reached the position; a proper master
 801                         // switchover already requires that the new master be caught up before the switch.
 802                         $replicationPos = $this->getSlavePos();
 803                         if ( $replicationPos && !$replicationPos->channelsMatch( $pos ) ) {
 804                                 $this->lastKnownReplicaPos = $replicationPos;
 805                                 $status = 0;
 806                         }
 807                 } elseif ( $status >= 0 ) {
 808                         // Remember that this position was reached to save queries next time
 809                         $this->lastKnownReplicaPos = $pos;
 810                 }
 811
 812                 return $status;
 813         }
 814
 815         /**
 816          * Get the position of the master from SHOW SLAVE STATUS
 817          *
 818          * @return MySQLMasterPos|bool
 819          */
 820         function getSlavePos() {
 821                 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__ );
 822                 $row = $this->fetchObject( $res );
 823
 824                 if ( $row ) {
 825                         $pos = isset( $row->Exec_master_log_pos )
 826                                 ? $row->Exec_master_log_pos
 827                                 : $row->Exec_Master_Log_Pos;
 828                         // Also fetch the last-applied GTID set (MariaDB)
 829                         if ( $this->useGTIDs ) {
 830                                 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'gtid_slave_pos'", __METHOD__ );
 831                                 $gtidRow = $this->fetchObject( $res );
 832                                 $gtidSet = $gtidRow ? $gtidRow->Value : '';
 833                         } else {
 834                                 $gtidSet = '';
 835                         }
 836
 837                         return new MySQLMasterPos( $row->Relay_Master_Log_File, $pos, $gtidSet );
 838                 } else {
 839                         return false;
 840                 }
 841         }
 842
 843         /**
 844          * Get the position of the master from SHOW MASTER STATUS
 845          *
 846          * @return MySQLMasterPos|bool
 847          */
 848         function getMasterPos() {
 849                 $res = $this->query( 'SHOW MASTER STATUS', __METHOD__ );
 850                 $row = $this->fetchObject( $res );
 851
 852                 if ( $row ) {
 853                         // Also fetch the last-written GTID set (MariaDB)
 854                         if ( $this->useGTIDs ) {
 855                                 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'gtid_binlog_pos'", __METHOD__ );
 856                                 $gtidRow = $this->fetchObject( $res );
 857                                 $gtidSet = $gtidRow ? $gtidRow->Value : '';
 858                         } else {
 859                                 $gtidSet = '';
 860                         }
 861
 862                         return new MySQLMasterPos( $row->File, $row->Position, $gtidSet );
 863                 } else {
 864                         return false;
 865                 }
 866         }
 867
 868         public function serverIsReadOnly() {
 869                 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'read_only'", __METHOD__ );
 870                 $row = $this->fetchObject( $res );
 871
 872                 return $row ? ( strtolower( $row->Value ) === 'on' ) : false;
 873         }
 874
 875         /**
 876          * @param string $index
 877          * @return string
 878          */
 879         function useIndexClause( $index ) {
 880                 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
 881         }
 882
 883         /**
 884          * @param string $index
 885          * @return string
 886          */
 887         function ignoreIndexClause( $index ) {
 888                 return "IGNORE INDEX (" . $this->indexName( $index ) . ")";
 889         }
 890
 891         /**
 892          * @return string
 893          */
 894         function lowPriorityOption() {
 895                 return 'LOW_PRIORITY';
 896         }
 897
 898         /**
 899          * @return string
 900          */
 901         public function getSoftwareLink() {
 902                 // MariaDB includes its name in its version string; this is how MariaDB's version of
 903                 // the mysql command-line client identifies MariaDB servers (see mariadb_connection()
 904                 // in libmysql/libmysql.c).
 905                 $version = $this->getServerVersion();
 906                 if ( strpos( $version, 'MariaDB' ) !== false || strpos( $version, '-maria-' ) !== false ) {
 907                         return '[{{int:version-db-mariadb-url}} MariaDB]';
 908                 }
 909
 910                 // Percona Server's version suffix is not very distinctive, and @@version_comment
 911                 // doesn't give the necessary info for source builds, so assume the server is MySQL.
 912                 // (Even Percona's version of mysql doesn't try to make the distinction.)
 913                 return '[{{int:version-db-mysql-url}} MySQL]';
 914         }
 915
 916         /**
 917          * @return string
 918          */
 919         public function getServerVersion() {
 920                 // Not using mysql_get_server_info() or similar for consistency: in the handshake,
 921                 // MariaDB 10 adds the prefix "5.5.5-", and only some newer client libraries strip
 922                 // it off (see RPL_VERSION_HACK in include/mysql_com.h).
 923                 if ( $this->serverVersion === null ) {
 924                         $this->serverVersion = $this->selectField( '', 'VERSION()', '', __METHOD__ );
 925                 }
 926                 return $this->serverVersion;
 927         }
 928
 929         /**
 930          * @param array $options
 931          */
 932         public function setSessionOptions( array $options ) {
 933                 if ( isset( $options['connTimeout'] ) ) {
 934                         $timeout = (int)$options['connTimeout'];
 935                         $this->query( "SET net_read_timeout=$timeout" );
 936                         $this->query( "SET net_write_timeout=$timeout" );
 937                 }
 938         }
 939
 940         /**
 941          * @param string $sql
 942          * @param string $newLine
 943          * @return bool
 944          */
 945         public function streamStatementEnd( &$sql, &$newLine ) {
 946                 if ( strtoupper( substr( $newLine, 0, 9 ) ) == 'DELIMITER' ) {
 947                         preg_match( '/^DELIMITER\s+(\S+)/', $newLine, $m );
 948                         $this->delimiter = $m[1];
 949                         $newLine = '';
 950                 }
 951
 952                 return parent::streamStatementEnd( $sql, $newLine );
 953         }
 954
 955         /**
 956          * Check to see if a named lock is available. This is non-blocking.
 957          *
 958          * @param string $lockName Name of lock to poll
 959          * @param string $method Name of method calling us
 960          * @return bool
 961          * @since 1.20
 962          */
 963         public function lockIsFree( $lockName, $method ) {
 964                 $lockName = $this->addQuotes( $this->makeLockName( $lockName ) );
 965                 $result = $this->query( "SELECT IS_FREE_LOCK($lockName) AS lockstatus", $method );
 966                 $row = $this->fetchObject( $result );
 967
 968                 return ( $row->lockstatus == 1 );
 969         }
 970
 971         /**
 972          * @param string $lockName
 973          * @param string $method
 974          * @param int $timeout
 975          * @return bool
 976          */
 977         public function lock( $lockName, $method, $timeout = 5 ) {
 978                 $lockName = $this->addQuotes( $this->makeLockName( $lockName ) );
 979                 $result = $this->query( "SELECT GET_LOCK($lockName, $timeout) AS lockstatus", $method );
 980                 $row = $this->fetchObject( $result );
 981
 982                 if ( $row->lockstatus == 1 ) {
 983                         parent::lock( $lockName, $method, $timeout ); // record
 984                         return true;
 985                 }
 986
 987                 wfDebug( __METHOD__ . " failed to acquire lock\n" );
 988
 989                 return false;
 990         }
 991
 992         /**
 993          * FROM MYSQL DOCS:
 994          * http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
 995          * @param string $lockName
 996          * @param string $method
 997          * @return bool
 998          */
 999         public function unlock( $lockName, $method ) {
1000                 $lockName = $this->addQuotes( $this->makeLockName( $lockName ) );
1001                 $result = $this->query( "SELECT RELEASE_LOCK($lockName) as lockstatus", $method );
1002                 $row = $this->fetchObject( $result );
1003
1004                 if ( $row->lockstatus == 1 ) {
1005                         parent::unlock( $lockName, $method ); // record
1006                         return true;
1007                 }
1008
1009                 wfDebug( __METHOD__ . " failed to release lock\n" );
1010
1011                 return false;
1012         }
1013
1014         private function makeLockName( $lockName ) {
1015                 // http://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1016                 // Newer version enforce a 64 char length limit.
1017                 return ( strlen( $lockName ) > 64 ) ? sha1( $lockName ) : $lockName;
1018         }
1019
1020         public function namedLocksEnqueue() {
1021                 return true;
1022         }
1023
1024         /**
1025          * @param array $read
1026          * @param array $write
1027          * @param string $method
1028          * @param bool $lowPriority
1029          * @return bool
1030          */
1031         public function lockTables( $read, $write, $method, $lowPriority = true ) {
1032                 $items = [];
1033
1034                 foreach ( $write as $table ) {
1035                         $tbl = $this->tableName( $table ) .
1036                                 ( $lowPriority ? ' LOW_PRIORITY' : '' ) .
1037                                 ' WRITE';
1038                         $items[] = $tbl;
1039                 }
1040                 foreach ( $read as $table ) {
1041                         $items[] = $this->tableName( $table ) . ' READ';
1042                 }
1043                 $sql = "LOCK TABLES " . implode( ',', $items );
1044                 $this->query( $sql, $method );
1045
1046                 return true;
1047         }
1048
1049         /**
1050          * @param string $method
1051          * @return bool
1052          */
1053         public function unlockTables( $method ) {
1054                 $this->query( "UNLOCK TABLES", $method );
1055
1056                 return true;
1057         }
1058
1059         /**
1060          * Get search engine class. All subclasses of this
1061          * need to implement this if they wish to use searching.
1062          *
1063          * @return string
1064          */
1065         public function getSearchEngine() {
1066                 return 'SearchMySQL';
1067         }
1068
1069         /**
1070          * @param bool $value
1071          */
1072         public function setBigSelects( $value = true ) {
1073                 if ( $value === 'default' ) {
1074                         if ( $this->mDefaultBigSelects === null ) {
1075                                 # Function hasn't been called before so it must already be set to the default
1076                                 return;
1077                         } else {
1078                                 $value = $this->mDefaultBigSelects;
1079                         }
1080                 } elseif ( $this->mDefaultBigSelects === null ) {
1081                         $this->mDefaultBigSelects =
1082                                 (bool)$this->selectField( false, '@@sql_big_selects', '', __METHOD__ );
1083                 }
1084                 $encValue = $value ? '1' : '0';
1085                 $this->query( "SET sql_big_selects=$encValue", __METHOD__ );
1086         }
1087
1088         /**
1089          * DELETE where the condition is a join. MySql uses multi-table deletes.
1090          * @param string $delTable
1091          * @param string $joinTable
1092          * @param string $delVar
1093          * @param string $joinVar
1094          * @param array|string $conds
1095          * @param bool|string $fname
1096          * @throws DBUnexpectedError
1097          * @return bool|ResultWrapper
1098          */
1099         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = __METHOD__ ) {
1100                 if ( !$conds ) {
1101                         throw new DBUnexpectedError( $this, 'DatabaseBase::deleteJoin() called with empty $conds' );
1102                 }
1103
1104                 $delTable = $this->tableName( $delTable );
1105                 $joinTable = $this->tableName( $joinTable );
1106                 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
1107
1108                 if ( $conds != '*' ) {
1109                         $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
1110                 }
1111
1112                 return $this->query( $sql, $fname );
1113         }
1114
1115         /**
1116          * @param string $table
1117          * @param array $rows
1118          * @param array $uniqueIndexes
1119          * @param array $set
1120          * @param string $fname
1121          * @return bool
1122          */
1123         public function upsert( $table, array $rows, array $uniqueIndexes,
1124                 array $set, $fname = __METHOD__
1125         ) {
1126                 if ( !count( $rows ) ) {
1127                         return true; // nothing to do
1128                 }
1129
1130                 if ( !is_array( reset( $rows ) ) ) {
1131                         $rows = [ $rows ];
1132                 }
1133
1134                 $table = $this->tableName( $table );
1135                 $columns = array_keys( $rows[0] );
1136
1137                 $sql = "INSERT INTO $table (" . implode( ',', $columns ) . ') VALUES ';
1138                 $rowTuples = [];
1139                 foreach ( $rows as $row ) {
1140                         $rowTuples[] = '(' . $this->makeList( $row ) . ')';
1141                 }
1142                 $sql .= implode( ',', $rowTuples );
1143                 $sql .= " ON DUPLICATE KEY UPDATE " . $this->makeList( $set, LIST_SET );
1144
1145                 return (bool)$this->query( $sql, $fname );
1146         }
1147
1148         /**
1149          * Determines how long the server has been up
1150          *
1151          * @return int
1152          */
1153         function getServerUptime() {
1154                 $vars = $this->getMysqlStatus( 'Uptime' );
1155
1156                 return (int)$vars['Uptime'];
1157         }
1158
1159         /**
1160          * Determines if the last failure was due to a deadlock
1161          *
1162          * @return bool
1163          */
1164         function wasDeadlock() {
1165                 return $this->lastErrno() == 1213;
1166         }
1167
1168         /**
1169          * Determines if the last failure was due to a lock timeout
1170          *
1171          * @return bool
1172          */
1173         function wasLockTimeout() {
1174                 return $this->lastErrno() == 1205;
1175         }
1176
1177         function wasErrorReissuable() {
1178                 return $this->lastErrno() == 2013 || $this->lastErrno() == 2006;
1179         }
1180
1181         /**
1182          * Determines if the last failure was due to the database being read-only.
1183          *
1184          * @return bool
1185          */
1186         function wasReadOnlyError() {
1187                 return $this->lastErrno() == 1223 ||
1188                         ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
1189         }
1190
1191         function wasConnectionError( $errno ) {
1192                 return $errno == 2013 || $errno == 2006;
1193         }
1194
1195         /**
1196          * Get the underlying binding handle, mConn
1197          *
1198          * Makes sure that mConn is set (disconnects and ping() failure can unset it).
1199          * This catches broken callers than catch and ignore disconnection exceptions.
1200          * Unlike checking isOpen(), this is safe to call inside of open().
1201          *
1202          * @return resource|object
1203          * @throws DBUnexpectedError
1204          * @since 1.26
1205          */
1206         protected function getBindingHandle() {
1207                 if ( !$this->mConn ) {
1208                         throw new DBUnexpectedError(
1209                                 $this,
1210                                 'DB connection was already closed or the connection dropped.'
1211                         );
1212                 }
1213
1214                 return $this->mConn;
1215         }
1216
1217         /**
1218          * @param string $oldName
1219          * @param string $newName
1220          * @param bool $temporary
1221          * @param string $fname
1222          * @return bool
1223          */
1224         function duplicateTableStructure( $oldName, $newName, $temporary = false, $fname = __METHOD__ ) {
1225                 $tmp = $temporary ? 'TEMPORARY ' : '';
1226                 $newName = $this->addIdentifierQuotes( $newName );
1227                 $oldName = $this->addIdentifierQuotes( $oldName );
1228                 $query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
1229
1230                 return $this->query( $query, $fname );
1231         }
1232
1233         /**
1234          * List all tables on the database
1235          *
1236          * @param string $prefix Only show tables with this prefix, e.g. mw_
1237          * @param string $fname Calling function name
1238          * @return array
1239          */
1240         function listTables( $prefix = null, $fname = __METHOD__ ) {
1241                 $result = $this->query( "SHOW TABLES", $fname );
1242
1243                 $endArray = [];
1244
1245                 foreach ( $result as $table ) {
1246                         $vars = get_object_vars( $table );
1247                         $table = array_pop( $vars );
1248
1249                         if ( !$prefix || strpos( $table, $prefix ) === 0 ) {
1250                                 $endArray[] = $table;
1251                         }
1252                 }
1253
1254                 return $endArray;
1255         }
1256
1257         /**
1258          * @param string $tableName
1259          * @param string $fName
1260          * @return bool|ResultWrapper
1261          */
1262         public function dropTable( $tableName, $fName = __METHOD__ ) {
1263                 if ( !$this->tableExists( $tableName, $fName ) ) {
1264                         return false;
1265                 }
1266
1267                 return $this->query( "DROP TABLE IF EXISTS " . $this->tableName( $tableName ), $fName );
1268         }
1269
1270         /**
1271          * @return array
1272          */
1273         protected function getDefaultSchemaVars() {
1274                 $vars = parent::getDefaultSchemaVars();
1275                 $vars['wgDBTableOptions'] = str_replace( 'TYPE', 'ENGINE', $GLOBALS['wgDBTableOptions'] );
1276                 $vars['wgDBTableOptions'] = str_replace(
1277                         'CHARSET=mysql4',
1278                         'CHARSET=binary',
1279                         $vars['wgDBTableOptions']
1280                 );
1281
1282                 return $vars;
1283         }
1284
1285         /**
1286          * Get status information from SHOW STATUS in an associative array
1287          *
1288          * @param string $which
1289          * @return array
1290          */
1291         function getMysqlStatus( $which = "%" ) {
1292                 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
1293                 $status = [];
1294
1295                 foreach ( $res as $row ) {
1296                         $status[$row->Variable_name] = $row->Value;
1297                 }
1298
1299                 return $status;
1300         }
1301
1302         /**
1303          * Lists VIEWs in the database
1304          *
1305          * @param string $prefix Only show VIEWs with this prefix, eg.
1306          * unit_test_, or $wgDBprefix. Default: null, would return all views.
1307          * @param string $fname Name of calling function
1308          * @return array
1309          * @since 1.22
1310          */
1311         public function listViews( $prefix = null, $fname = __METHOD__ ) {
1312
1313                 if ( !isset( $this->allViews ) ) {
1314
1315                         // The name of the column containing the name of the VIEW
1316                         $propertyName = 'Tables_in_' . $this->mDBname;
1317
1318                         // Query for the VIEWS
1319                         $result = $this->query( 'SHOW FULL TABLES WHERE TABLE_TYPE = "VIEW"' );
1320                         $this->allViews = [];
1321                         while ( ( $row = $this->fetchRow( $result ) ) !== false ) {
1322                                 array_push( $this->allViews, $row[$propertyName] );
1323                         }
1324                 }
1325
1326                 if ( is_null( $prefix ) || $prefix === '' ) {
1327                         return $this->allViews;
1328                 }
1329
1330                 $filteredViews = [];
1331                 foreach ( $this->allViews as $viewName ) {
1332                         // Does the name of this VIEW start with the table-prefix?
1333                         if ( strpos( $viewName, $prefix ) === 0 ) {
1334                                 array_push( $filteredViews, $viewName );
1335                         }
1336                 }
1337
1338                 return $filteredViews;
1339         }
1340
1341         /**
1342          * Differentiates between a TABLE and a VIEW.
1343          *
1344          * @param string $name Name of the TABLE/VIEW to test
1345          * @param string $prefix
1346          * @return bool
1347          * @since 1.22
1348          */
1349         public function isView( $name, $prefix = null ) {
1350                 return in_array( $name, $this->listViews( $prefix ) );
1351         }
1352 }
1353
1354 /**
1355  * Utility class.
1356  * @ingroup Database
1357  */
1358 class MySQLField implements Field {
1359         private $name, $tablename, $default, $max_length, $nullable,
1360                 $is_pk, $is_unique, $is_multiple, $is_key, $type, $binary,
1361                 $is_numeric, $is_blob, $is_unsigned, $is_zerofill;
1362
1363         function __construct( $info ) {
1364                 $this->name = $info->name;
1365                 $this->tablename = $info->table;
1366                 $this->default = $info->def;
1367                 $this->max_length = $info->max_length;
1368                 $this->nullable = !$info->not_null;
1369                 $this->is_pk = $info->primary_key;
1370                 $this->is_unique = $info->unique_key;
1371                 $this->is_multiple = $info->multiple_key;
1372                 $this->is_key = ( $this->is_pk || $this->is_unique || $this->is_multiple );
1373                 $this->type = $info->type;
1374                 $this->binary = isset( $info->binary ) ? $info->binary : false;
1375                 $this->is_numeric = isset( $info->numeric ) ? $info->numeric : false;
1376                 $this->is_blob = isset( $info->blob ) ? $info->blob : false;
1377                 $this->is_unsigned = isset( $info->unsigned ) ? $info->unsigned : false;
1378                 $this->is_zerofill = isset( $info->zerofill ) ? $info->zerofill : false;
1379         }
1380
1381         /**
1382          * @return string
1383          */
1384         function name() {
1385                 return $this->name;
1386         }
1387
1388         /**
1389          * @return string
1390          */
1391         function tableName() {
1392                 return $this->tablename;
1393         }
1394
1395         /**
1396          * @return string
1397          */
1398         function type() {
1399                 return $this->type;
1400         }
1401
1402         /**
1403          * @return bool
1404          */
1405         function isNullable() {
1406                 return $this->nullable;
1407         }
1408
1409         function defaultValue() {
1410                 return $this->default;
1411         }
1412
1413         /**
1414          * @return bool
1415          */
1416         function isKey() {
1417                 return $this->is_key;
1418         }
1419
1420         /**
1421          * @return bool
1422          */
1423         function isMultipleKey() {
1424                 return $this->is_multiple;
1425         }
1426
1427         /**
1428          * @return bool
1429          */
1430         function isBinary() {
1431                 return $this->binary;
1432         }
1433
1434         /**
1435          * @return bool
1436          */
1437         function isNumeric() {
1438                 return $this->is_numeric;
1439         }
1440
1441         /**
1442          * @return bool
1443          */
1444         function isBlob() {
1445                 return $this->is_blob;
1446         }
1447
1448         /**
1449          * @return bool
1450          */
1451         function isUnsigned() {
1452                 return $this->is_unsigned;
1453         }
1454
1455         /**
1456          * @return bool
1457          */
1458         function isZerofill() {
1459                 return $this->is_zerofill;
1460         }
1461 }
1462
1463 /**
1464  * DBMasterPos class for MySQL/MariaDB
1465  *
1466  * Note that master positions and sync logic here make some assumptions:
1467  *  - Binlog-based usage assumes single-source replication and non-hierarchical replication.
1468  *  - GTID-based usage allows getting/syncing with multi-source replication. It is assumed
1469  *    that GTID sets are complete (e.g. include all domains on the server).
1470  */
1471 class MySQLMasterPos implements DBMasterPos {
1472         /** @var string Binlog file */
1473         public $file;
1474         /** @var int Binglog file position */
1475         public $pos;
1476         /** @var string[] GTID list */
1477         public $gtids = [];
1478         /** @var float UNIX timestamp */
1479         public $asOfTime = 0.0;
1480
1481         /**
1482          * @param string $file Binlog file name
1483          * @param integer $pos Binlog position
1484          * @param string $gtid Comma separated GTID set [optional]
1485          */
1486         function __construct( $file, $pos, $gtid = '' ) {
1487                 $this->file = $file;
1488                 $this->pos = $pos;
1489                 $this->gtids = array_map( 'trim', explode( ',', $gtid ) );
1490                 $this->asOfTime = microtime( true );
1491         }
1492
1493         /**
1494          * @return string <binlog file>/<position>, e.g db1034-bin.000976/843431247
1495          */
1496         function __toString() {
1497                 return "{$this->file}/{$this->pos}";
1498         }
1499
1500         function asOfTime() {
1501                 return $this->asOfTime;
1502         }
1503
1504         function hasReached( DBMasterPos $pos ) {
1505                 if ( !( $pos instanceof self ) ) {
1506                         throw new InvalidArgumentException( "Position not an instance of " . __CLASS__ );
1507                 }
1508
1509                 // Prefer GTID comparisons, which work with multi-tier replication
1510                 $thisPosByDomain = $this->getGtidCoordinates();
1511                 $thatPosByDomain = $pos->getGtidCoordinates();
1512                 if ( $thisPosByDomain && $thatPosByDomain ) {
1513                         $reached = true;
1514                         // Check that this has positions GTE all of those in $pos for all domains in $pos
1515                         foreach ( $thatPosByDomain as $domain => $thatPos ) {
1516                                 $thisPos = isset( $thisPosByDomain[$domain] ) ? $thisPosByDomain[$domain] : -1;
1517                                 $reached = $reached && ( $thatPos <= $thisPos );
1518                         }
1519
1520                         return $reached;
1521                 }
1522
1523                 // Fallback to the binlog file comparisons
1524                 $thisBinPos = $this->getBinlogCoordinates();
1525                 $thatBinPos = $pos->getBinlogCoordinates();
1526                 if ( $thisBinPos && $thatBinPos && $thisBinPos['binlog'] === $thatBinPos['binlog'] ) {
1527                         return ( $thisBinPos['pos'] >= $thatBinPos['pos'] );
1528                 }
1529
1530                 // Comparing totally different binlogs does not make sense
1531                 return false;
1532         }
1533
1534         function channelsMatch( DBMasterPos $pos ) {
1535                 if ( !( $pos instanceof self ) ) {
1536                         throw new InvalidArgumentException( "Position not an instance of " . __CLASS__ );
1537                 }
1538
1539                 // Prefer GTID comparisons, which work with multi-tier replication
1540                 $thisPosDomains = array_keys( $this->getGtidCoordinates() );
1541                 $thatPosDomains = array_keys( $pos->getGtidCoordinates() );
1542                 if ( $thisPosDomains && $thatPosDomains ) {
1543                         // Check that this has GTIDs for all domains in $pos
1544                         return !array_diff( $thatPosDomains, $thisPosDomains );
1545                 }
1546
1547                 // Fallback to the binlog file comparisons
1548                 $thisBinPos = $this->getBinlogCoordinates();
1549                 $thatBinPos = $pos->getBinlogCoordinates();
1550
1551                 return ( $thisBinPos && $thatBinPos && $thisBinPos['binlog'] === $thatBinPos['binlog'] );
1552         }
1553
1554         /**
1555          * @note: this returns false for multi-source replication GTID sets
1556          * @see https://mariadb.com/kb/en/mariadb/gtid
1557          * @see https://dev.mysql.com/doc/refman/5.6/en/replication-gtids-concepts.html
1558          * @return array Map of (domain => integer position) or false
1559          */
1560         protected function getGtidCoordinates() {
1561                 $gtidInfos = [];
1562                 foreach ( $this->gtids as $gtid ) {
1563                         $m = [];
1564                         // MariaDB style: <domain>-<server id>-<sequence number>
1565                         if ( preg_match( '!^(\d+)-\d+-(\d+)$!', $gtid, $m ) ) {
1566                                 $gtidInfos[(int)$m[1]] = (int)$m[2];
1567                         // MySQL style: <UUID domain>:<sequence number>
1568                         } elseif ( preg_match( '!^(\w{8}-\w{4}-\w{4}-\w{4}-\w{12}):(\d+)$!', $gtid, $m ) ) {
1569                                 $gtidInfos[$m[1]] = (int)$m[2];
1570                         } else {
1571                                 $gtidInfos = [];
1572                                 break; // unrecognized GTID
1573                         }
1574
1575                 }
1576
1577                 return $gtidInfos;
1578         }
1579
1580         /**
1581          * @see http://dev.mysql.com/doc/refman/5.7/en/show-master-status.html
1582          * @see http://dev.mysql.com/doc/refman/5.7/en/show-slave-status.html
1583          * @return array|bool (binlog, (integer file number, integer position)) or false
1584          */
1585         protected function getBinlogCoordinates() {
1586                 $m = [];
1587                 if ( preg_match( '!^(.+)\.(\d+)/(\d+)$!', (string)$this, $m ) ) {
1588                         return [ 'binlog' => $m[1], 'pos' => [ (int)$m[2], (int)$m[3] ] ];
1589                 }
1590
1591                 return false;
1592         }
1593 }