includes/Database.php

   1 <?php
   2 /**
   3  * This file deals with MySQL interface functions
   4  * and query specifics/optimisations
   5  * @version # $Id$
   6  * @package MediaWiki
   7  */
   8
   9 /**
  10  * Depends on the CacheManager
  11  */
  12 require_once( 'CacheManager.php' );
  13
  14 /** @todo document */
  15 define( 'LIST_COMMA', 0 );
  16 /** @todo document */
  17 define( 'LIST_AND', 1 );
  18 /** @todo document */
  19 define( 'LIST_SET', 2 );
  20 /** @todo document */
  21 define( 'LIST_NAMES', 3);
  22
  23 /** Number of times to re-try an operation in case of deadlock */
  24 define( 'DEADLOCK_TRIES', 4 );
  25 /** Minimum time to wait before retry, in microseconds */
  26 define( 'DEADLOCK_DELAY_MIN', 500000 );
  27 /** Maximum time to wait before retry */
  28 define( 'DEADLOCK_DELAY_MAX', 1500000 );
  29
  30 /**
  31  * Database abstraction object
  32  * @package MediaWiki
  33  * @version # $Id$
  34  */
  35 class Database {
  36
  37 #------------------------------------------------------------------------------
  38 # Variables
  39 #------------------------------------------------------------------------------
  40         /**#@+
  41          * @access private
  42          */
  43         var $mLastQuery = '';
  44
  45         var $mServer, $mUser, $mPassword, $mConn, $mDBname;
  46         var $mOut, $mOpened = false;
  47
  48         var $mFailFunction;
  49         var $mTablePrefix;
  50         var $mFlags;
  51         var $mTrxLevel = 0;
  52         /**#@-*/
  53
  54 #------------------------------------------------------------------------------
  55 # Accessors
  56 #------------------------------------------------------------------------------
  57         # These optionally set a variable and return the previous state
  58
  59         /**
  60          * Fail function, takes a Database as a parameter
  61          * Set to false for default, 1 for ignore errors
  62          */
  63         function failFunction( $function = NULL ) {
  64                 return wfSetVar( $this->mFailFunction, $function );
  65         }
  66
  67         /**
  68          * Output page, used for reporting errors
  69          * FALSE means discard output
  70          */
  71         function &setOutputPage( &$out ) {
  72                 $this->mOut =& $out;
  73         }
  74
  75         /**
  76          * Boolean, controls output of large amounts of debug information
  77          */
  78         function debug( $debug = NULL ) {
  79                 return wfSetBit( $this->mFlags, DBO_DEBUG, $debug );
  80         }
  81
  82         /**
  83          * Turns buffering of SQL result sets on (true) or off (false).
  84          * Default is "on" and it should not be changed without good reasons.
  85          */
  86         function bufferResults( $buffer = NULL ) {
  87                 if ( is_null( $buffer ) ) {
  88                         return !(bool)( $this->mFlags & DBO_NOBUFFER );
  89                 } else {
  90                         return !wfSetBit( $this->mFlags, DBO_NOBUFFER, !$buffer );
  91                 }
  92         }
  93
  94         /**
  95          * Turns on (false) or off (true) the automatic generation and sending
  96          * of a "we're sorry, but there has been a database error" page on
  97          * database errors. Default is on (false). When turned off, the
  98          * code should use wfLastErrno() and wfLastError() to handle the
  99          * situation as appropriate.
 100          */
 101         function ignoreErrors( $ignoreErrors = NULL ) {
 102                 return wfSetBit( $this->mFlags, DBO_IGNORE, $ignoreErrors );
 103         }
 104
 105         /**
 106          * The current depth of nested transactions
 107          * @param integer $level
 108          */
 109         function trxLevel( $level = NULL ) {
 110                 return wfSetVar( $this->mTrxLevel, $level );
 111         }
 112
 113         /**#@+
 114          * Get function
 115          */
 116         function lastQuery() { return $this->mLastQuery; }
 117         function isOpen() { return $this->mOpened; }
 118         /**#@-*/
 119
 120 #------------------------------------------------------------------------------
 121 # Other functions
 122 #------------------------------------------------------------------------------
 123
 124         /**#@+
 125          * @param string $server database server host
 126          * @param string $user database user name
 127          * @param string $password database user password
 128          * @param string $dbname database name
 129          */
 130
 131         /**
 132          * @param failFunction
 133          * @param $flags
 134          * @param string $tablePrefix Database table prefixes. By default use the prefix gave in LocalSettings.php
 135          */
 136         function Database( $server = false, $user = false, $password = false, $dbName = false,
 137                 $failFunction = false, $flags = 0, $tablePrefix = 'get from global' ) {
 138
 139                 global $wgOut, $wgDBprefix, $wgCommandLineMode;
 140                 # Can't get a reference if it hasn't been set yet
 141                 if ( !isset( $wgOut ) ) {
 142                         $wgOut = NULL;
 143                 }
 144                 $this->mOut =& $wgOut;
 145
 146                 $this->mFailFunction = $failFunction;
 147                 $this->mFlags = $flags;
 148
 149                 if ( $this->mFlags & DBO_DEFAULT ) {
 150                         if ( $wgCommandLineMode ) {
 151                                 $this->mFlags &= ~DBO_TRX;
 152                         } else {
 153                                 $this->mFlags |= DBO_TRX;
 154                         }
 155                 }
 156
 157                 /** Get the default table prefix*/
 158                 if ( $tablePrefix == 'get from global' ) {
 159                         $this->mTablePrefix = $wgDBprefix;
 160                 } else {
 161                         $this->mTablePrefix = $tablePrefix;
 162                 }
 163
 164                 if ( $server ) {
 165                         $this->open( $server, $user, $password, $dbName );
 166                 }
 167         }
 168
 169         /**
 170          * @static
 171          * @param failFunction
 172          * @param $flags
 173          */
 174         function newFromParams( $server, $user, $password, $dbName,
 175                 $failFunction = false, $flags = 0 )
 176         {
 177                 return new Database( $server, $user, $password, $dbName, $failFunction, $flags );
 178         }
 179
 180         /**
 181          * Usually aborts on failure
 182          * If the failFunction is set to a non-zero integer, returns success
 183          */
 184         function open( $server, $user, $password, $dbName ) {
 185                 # Test for missing mysql.so
 186                 # Otherwise we get a suppressed fatal error, which is very hard to track down
 187                 if ( !function_exists( 'mysql_connect' ) ) {
 188                         die( "MySQL functions missing, have you compiled PHP with the --with-mysql option?\n" );
 189                 }
 190
 191                 $this->close();
 192                 $this->mServer = $server;
 193                 $this->mUser = $user;
 194                 $this->mPassword = $password;
 195                 $this->mDBname = $dbName;
 196
 197                 $success = false;
 198
 199                 @/**/$this->mConn = mysql_connect( $server, $user, $password );
 200                 if ( $dbName != '' ) {
 201                         if ( $this->mConn !== false ) {
 202                                 $success = @/**/mysql_select_db( $dbName, $this->mConn );
 203                                 if ( !$success ) {
 204                                         wfDebug( "Error selecting database \"$dbName\": " . $this->lastError() . "\n" );
 205                                 }
 206                         } else {
 207                                 wfDebug( "DB connection error\n" );
 208                                 wfDebug( "Server: $server, User: $user, Password: " .
 209                                         substr( $password, 0, 3 ) . "...\n" );
 210                                 $success = false;
 211                         }
 212                 } else {
 213                         # Delay USE query
 214                         $success = !!$this->mConn;
 215                 }
 216
 217                 if ( !$success ) {
 218                         $this->reportConnectionError();
 219                         $this->close();
 220                 }
 221                 $this->mOpened = $success;
 222                 return $success;
 223         }
 224         /**#@-*/
 225
 226         /**
 227          * Closes a database connection.
 228          * if it is open : commits any open transactions
 229          *
 230          * @return bool operation success. true if already closed.
 231          */
 232         function close()
 233         {
 234                 $this->mOpened = false;
 235                 if ( $this->mConn ) {
 236                         if ( $this->trxLevel() ) {
 237                                 $this->immediateCommit();
 238                         }
 239                         return mysql_close( $this->mConn );
 240                 } else {
 241                         return true;
 242                 }
 243         }
 244
 245         /**
 246          * @access private
 247          * @param string $msg error message ?
 248          * @todo parameter $msg is not used
 249          */
 250         function reportConnectionError( $msg = '') {
 251                 if ( $this->mFailFunction ) {
 252                         if ( !is_int( $this->mFailFunction ) ) {
 253                                 $ff = $this->mFailFunction;
 254                                 $ff( $this, mysql_error() );
 255                         }
 256                 } else {
 257                         wfEmergencyAbort( $this, mysql_error() );
 258                 }
 259         }
 260
 261         /**
 262          * Usually aborts on failure
 263          * If errors are explicitly ignored, returns success
 264          */
 265         function query( $sql, $fname = '', $tempIgnore = false ) {
 266                 global $wgProfiling, $wgCommandLineMode;
 267
 268                 if ( $wgProfiling ) {
 269                         # generalizeSQL will probably cut down the query to reasonable
 270                         # logging size most of the time. The substr is really just a sanity check.
 271                         $profName = 'query: ' . substr( Database::generalizeSQL( $sql ), 0, 255 );
 272                         wfProfileIn( $profName );
 273                 }
 274
 275                 $this->mLastQuery = $sql;
 276
 277                 if ( $this->debug() ) {
 278                         $sqlx = substr( $sql, 0, 500 );
 279                         $sqlx = wordwrap(strtr($sqlx,"\t\n",'  '));
 280                         wfDebug( "SQL: $sqlx\n" );
 281                 }
 282                 # Add a comment for easy SHOW PROCESSLIST interpretation
 283                 if ( $fname ) {
 284                         $commentedSql = "/* $fname */ $sql";
 285                 } else {
 286                         $commentedSql = $sql;
 287                 }
 288
 289                 # If DBO_TRX is set, start a transaction
 290                 if ( ( $this->mFlags & DBO_TRX ) && !$this->trxLevel() && $sql != 'BEGIN' ) {
 291                         $this->begin();
 292                 }
 293
 294                 # Do the query and handle errors
 295                 $ret = $this->doQuery( $commentedSql );
 296                 if ( false === $ret ) {
 297                         $this->reportQueryError( $this->lastError(), $this->lastErrno(), $sql, $fname, $tempIgnore );
 298                 }
 299
 300                 if ( $wgProfiling ) {
 301                         wfProfileOut( $profName );
 302                 }
 303                 return $ret;
 304         }
 305
 306         /**
 307          * The DBMS-dependent part of query()
 308          * @param string $sql SQL query.
 309          */
 310         function doQuery( $sql ) {
 311                 if( $this->bufferResults() ) {
 312                         $ret = mysql_query( $sql, $this->mConn );
 313                 } else {
 314                         $ret = mysql_unbuffered_query( $sql, $this->mConn );
 315                 }
 316                 return $ret;
 317         }
 318
 319         /**
 320          * @param $error
 321          * @param $errno
 322          * @param $sql
 323          * @param string $fname
 324          * @param bool $tempIgnore
 325          */
 326         function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
 327                 global $wgCommandLineMode, $wgFullyInitialised;
 328                 # Ignore errors during error handling to avoid infinite recursion
 329                 $ignore = $this->ignoreErrors( true );
 330
 331                 if( $ignore || $tempIgnore ) {
 332                         wfDebug("SQL ERROR (ignored): " . $error . "\n");
 333                 } else {
 334                         $sql1line = str_replace( "\n", "\\n", $sql );
 335                         wfLogDBError("$fname\t$errno\t$error\t$sql1line\n");
 336                         wfDebug("SQL ERROR: " . $error . "\n");
 337                         if ( $wgCommandLineMode || !$this->mOut || empty( $wgFullyInitialised ) ) {
 338                                 $message = "A database error has occurred\n" .
 339                                   "Query: $sql\n" .
 340                                   "Function: $fname\n" .
 341                                   "Error: $errno $error\n";
 342                                 if ( !$wgCommandLineMode ) {
 343                                         $message = nl2br( $message );
 344                                 }
 345                                 wfDebugDieBacktrace( $message );
 346                         } else {
 347                                 // this calls wfAbruptExit()
 348                                 $this->mOut->databaseError( $fname, $sql, $error, $errno );
 349                         }
 350                 }
 351                 $this->ignoreErrors( $ignore );
 352         }
 353
 354
 355         /**#@+
 356          * @param mixed $res A SQL result
 357          */
 358         /**
 359          * @todo document
 360          */
 361         function freeResult( $res ) {
 362                 if ( !@/**/mysql_free_result( $res ) ) {
 363                         wfDebugDieBacktrace( "Unable to free MySQL result\n" );
 364                 }
 365         }
 366
 367         /**
 368          * @todo FIXME: HACK HACK HACK HACK debug
 369          */
 370         function fetchObject( $res ) {
 371                 @/**/$row = mysql_fetch_object( $res );
 372                 # FIXME: HACK HACK HACK HACK debug
 373                 if( mysql_errno() ) {
 374                         wfDebugDieBacktrace( 'Error in fetchObject(): ' . htmlspecialchars( mysql_error() ) );
 375                 }
 376                 return $row;
 377         }
 378
 379         /**
 380          * @todo document
 381          */
 382         function fetchRow( $res ) {
 383                 @/**/$row = mysql_fetch_array( $res );
 384                 if (mysql_errno() ) {
 385                         wfDebugDieBacktrace( 'Error in fetchRow(): ' . htmlspecialchars( mysql_error() ) );
 386                 }
 387                 return $row;
 388         }
 389
 390         /**
 391          * @todo document
 392          */
 393         function numRows( $res ) {
 394                 @/**/$n = mysql_num_rows( $res );
 395                 if( mysql_errno() ) {
 396                         wfDebugDieBacktrace( 'Error in numRows(): ' . htmlspecialchars( mysql_error() ) );
 397                 }
 398                 return $n;
 399         }
 400
 401         /**
 402          * @todo document
 403          */
 404         function numFields( $res ) { return mysql_num_fields( $res ); }
 405
 406         /**
 407          * @todo document
 408          */
 409         function fieldName( $res, $n ) { return mysql_field_name( $res, $n ); }
 410         /**
 411          * @todo document
 412          */
 413         function insertId() { return mysql_insert_id( $this->mConn ); }
 414         /**
 415          * @todo document
 416          */
 417         function dataSeek( $res, $row ) { return mysql_data_seek( $res, $row ); }
 418         /**
 419          * @todo document
 420          */
 421         function lastErrno() { return mysql_errno(); }
 422         /**
 423          * @todo document
 424          */
 425         function lastError() { return mysql_error(); }
 426         /**
 427          * @todo document
 428          */
 429         function affectedRows() { return mysql_affected_rows( $this->mConn ); }
 430         /**#@-*/ // end of template : @param $result
 431
 432         /**
 433          * Simple UPDATE wrapper
 434          * Usually aborts on failure
 435          * If errors are explicitly ignored, returns success
 436          *
 437          * This function exists for historical reasons, Database::update() has a more standard
 438          * calling convention and feature set
 439          */
 440         function set( $table, $var, $value, $cond, $fname = 'Database::set' )
 441         {
 442                 $table = $this->tableName( $table );
 443                 $sql = "UPDATE $table SET $var = '" .
 444                   $this->strencode( $value ) . "' WHERE ($cond)";
 445                 return !!$this->query( $sql, DB_MASTER, $fname );
 446         }
 447
 448         /**
 449          * @todo document
 450          */
 451         function getField( $table, $var, $cond='', $fname = 'Database::getField', $options = array() ) {
 452                 return $this->selectField( $table, $var, $cond, $fname = 'Database::get', $options = array() );
 453         }
 454
 455         /**
 456          * Simple SELECT wrapper, returns a single field, input must be encoded
 457          * Usually aborts on failure
 458          * If errors are explicitly ignored, returns FALSE on failure
 459          */
 460         function selectField( $table, $var, $cond='', $fname = 'Database::selectField', $options = array() ) {
 461                 if ( !is_array( $options ) ) {
 462                         $options = array( $options );
 463                 }
 464                 $options['LIMIT'] = 1;
 465
 466                 $res = $this->select( $table, $var, $cond, $fname, $options );
 467                 if ( $res === false || !$this->numRows( $res ) ) {
 468                         return false;
 469                 }
 470                 $row = $this->fetchRow( $res );
 471                 if ( $row !== false ) {
 472                         $this->freeResult( $res );
 473                         return $row[0];
 474                 } else {
 475                         return false;
 476                 }
 477         }
 478
 479         /**
 480          * Returns an optional USE INDEX clause to go after the table, and a
 481          * string to go at the end of the query
 482          */
 483         function makeSelectOptions( $options ) {
 484                 if ( !is_array( $options ) ) {
 485                         $options = array( $options );
 486                 }
 487
 488                 $tailOpts = '';
 489
 490                 if ( isset( $options['ORDER BY'] ) ) {
 491                         $tailOpts .= " ORDER BY {$options['ORDER BY']}";
 492                 }
 493                 if ( isset( $options['LIMIT'] ) ) {
 494                         $tailOpts .= " LIMIT {$options['LIMIT']}";
 495                 }
 496
 497                 if ( is_numeric( array_search( 'FOR UPDATE', $options ) ) ) {
 498                         $tailOpts .= ' FOR UPDATE';
 499                 }
 500
 501                 if ( is_numeric( array_search( 'LOCK IN SHARE MODE', $options ) ) ) {
 502                         $tailOpts .= ' LOCK IN SHARE MODE';
 503                 }
 504
 505                 if ( isset( $options['USE INDEX'] ) ) {
 506                         $useIndex = $this->useIndexClause( $options['USE INDEX'] );
 507                 } else {
 508                         $useIndex = '';
 509                 }
 510                 return array( $useIndex, $tailOpts );
 511         }
 512
 513         /**
 514          * SELECT wrapper
 515          */
 516         function select( $table, $vars, $conds='', $fname = 'Database::select', $options = array() )
 517         {
 518                 if ( is_array( $vars ) ) {
 519                         $vars = implode( ',', $vars );
 520                 }
 521                 if ($table!='')
 522                         $from = ' FROM ' .$this->tableName( $table );
 523                 else
 524                         $from = '';
 525
 526                 list( $useIndex, $tailOpts ) = $this->makeSelectOptions( $options );
 527
 528                 if ( $conds !== false && $conds != '' ) {
 529                         if ( is_array( $conds ) ) {
 530                                 $conds = $this->makeList( $conds, LIST_AND );
 531                         }
 532                         $sql = "SELECT $vars $from $useIndex WHERE $conds $tailOpts";
 533                 } else {
 534                         $sql = "SELECT $vars $from $useIndex $tailOpts";
 535                 }
 536                 return $this->query( $sql, $fname );
 537         }
 538
 539         /**
 540          * @todo document
 541          */
 542         function getArray( $table, $vars, $conds, $fname = 'Database::getArray', $options = array() ) {
 543                 return $this->selectRow( $table, $vars, $conds, $fname, $options );
 544         }
 545
 546
 547         /**
 548          * Single row SELECT wrapper
 549          * Aborts or returns FALSE on error
 550          *
 551          * $vars: the selected variables
 552          * $conds: a condition map, terms are ANDed together.
 553          *   Items with numeric keys are taken to be literal conditions
 554          * Takes an array of selected variables, and a condition map, which is ANDed
 555          * e.g. selectRow( "cur", array( "cur_id" ), array( "cur_namespace" => 0, "cur_title" => "Astronomy" ) )
 556          *   would return an object where $obj->cur_id is the ID of the Astronomy article
 557          *
 558          * @todo migrate documentation to phpdocumentor format
 559          */
 560         function selectRow( $table, $vars, $conds, $fname = 'Database::selectRow', $options = array() ) {
 561                 $options['LIMIT'] = 1;
 562                 $res = $this->select( $table, $vars, $conds, $fname, $options );
 563                 if ( $res === false || !$this->numRows( $res ) ) {
 564                         return false;
 565                 }
 566                 $obj = $this->fetchObject( $res );
 567                 $this->freeResult( $res );
 568                 return $obj;
 569
 570         }
 571
 572         /**
 573          * Removes most variables from an SQL query and replaces them with X or N for numbers.
 574          * It's only slightly flawed. Don't use for anything important.
 575          *
 576          * @param string $sql A SQL Query
 577          * @static
 578          */
 579         function generalizeSQL( $sql ) {
 580                 # This does the same as the regexp below would do, but in such a way
 581                 # as to avoid crashing php on some large strings.
 582                 # $sql = preg_replace ( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql);
 583
 584                 $sql = str_replace ( "\\\\", '', $sql);
 585                 $sql = str_replace ( "\\'", '', $sql);
 586                 $sql = str_replace ( "\\\"", '', $sql);
 587                 $sql = preg_replace ("/'.*'/s", "'X'", $sql);
 588                 $sql = preg_replace ('/".*"/s', "'X'", $sql);
 589
 590                 # All newlines, tabs, etc replaced by single space
 591                 $sql = preg_replace ( "/\s+/", ' ', $sql);
 592
 593                 # All numbers => N
 594                 $sql = preg_replace ('/-?[0-9]+/s', 'N', $sql);
 595
 596                 return $sql;
 597         }
 598
 599         /**
 600          * Determines whether a field exists in a table
 601          * Usually aborts on failure
 602          * If errors are explicitly ignored, returns NULL on failure
 603          */
 604         function fieldExists( $table, $field, $fname = 'Database::fieldExists' ) {
 605                 $table = $this->tableName( $table );
 606                 $res = $this->query( 'DESCRIBE '.$table, DB_SLAVE, $fname );
 607                 if ( !$res ) {
 608                         return NULL;
 609                 }
 610
 611                 $found = false;
 612
 613                 while ( $row = $this->fetchObject( $res ) ) {
 614                         if ( $row->Field == $field ) {
 615                                 $found = true;
 616                                 break;
 617                         }
 618                 }
 619                 return $found;
 620         }
 621
 622         /**
 623          * Determines whether an index exists
 624          * Usually aborts on failure
 625          * If errors are explicitly ignored, returns NULL on failure
 626          */
 627         function indexExists( $table, $index, $fname = 'Database::indexExists' ) {
 628                 $info = $this->indexInfo( $table, $index, $fname );
 629                 if ( is_null( $info ) ) {
 630                         return NULL;
 631                 } else {
 632                         return $info !== false;
 633                 }
 634         }
 635
 636
 637         /**
 638          * @todo document
 639          */
 640         function indexInfo( $table, $index, $fname = 'Database::indexInfo' ) {
 641                 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
 642                 # SHOW INDEX should work for 3.x and up:
 643                 # http://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
 644                 $table = $this->tableName( $table );
 645                 $sql = 'SHOW INDEX FROM '.$table;
 646                 $res = $this->query( $sql, $fname );
 647                 if ( !$res ) {
 648                         return NULL;
 649                 }
 650
 651                 while ( $row = $this->fetchObject( $res ) ) {
 652                         if ( $row->Key_name == $index ) {
 653                                 return $row;
 654                         }
 655                 }
 656                 return false;
 657         }
 658
 659         /**
 660          * @param $table
 661          * @todo document
 662          */
 663         function tableExists( $table ) {
 664                 $table = $this->tableName( $table );
 665                 $old = $this->ignoreErrors( true );
 666                 $res = $this->query( "SELECT 1 FROM $table LIMIT 1" );
 667                 $this->ignoreErrors( $old );
 668                 if( $res ) {
 669                         $this->freeResult( $res );
 670                         return true;
 671                 } else {
 672                         return false;
 673                 }
 674         }
 675
 676         /**
 677          * @param $table
 678          * @param $field
 679          * @todo document
 680          */
 681         function fieldInfo( $table, $field ) {
 682                 $table = $this->tableName( $table );
 683                 $res = $this->query( "SELECT * FROM $table LIMIT 1" );
 684                 $n = mysql_num_fields( $res );
 685                 for( $i = 0; $i < $n; $i++ ) {
 686                         $meta = mysql_fetch_field( $res, $i );
 687                         if( $field == $meta->name ) {
 688                                 return $meta;
 689                         }
 690                 }
 691                 return false;
 692         }
 693
 694         /**
 695          * @todo document
 696          */
 697         function fieldType( $res, $index ) {
 698                 return mysql_field_type( $res, $index );
 699         }
 700
 701         /**
 702          * @todo document
 703          */
 704         function indexUnique( $table, $index ) {
 705                 $indexInfo = $this->indexInfo( $table, $index );
 706                 if ( !$indexInfo ) {
 707                         return NULL;
 708                 }
 709                 return !$indexInfo->Non_unique;
 710         }
 711
 712         /**
 713          * @todo document
 714          */
 715         function insertArray( $table, $a, $fname = 'Database::insertArray', $options = array() ) {
 716                 return $this->insert( $table, $a, $fname = 'Database::insertArray', $options = array() );
 717         }
 718
 719         /**
 720          * INSERT wrapper, inserts an array into a table
 721          *
 722          * $a may be a single associative array, or an array of these with numeric keys, for
 723          * multi-row insert.
 724          *
 725          * Usually aborts on failure
 726          * If errors are explicitly ignored, returns success
 727          */
 728         function insert( $table, $a, $fname = 'Database::insert', $options = array() ) {
 729                 # No rows to insert, easy just return now
 730                 if ( !count( $a ) ) {
 731                         return true;
 732                 }
 733
 734                 $table = $this->tableName( $table );
 735                 if ( !is_array( $options ) ) {
 736                         $options = array( $options );
 737                 }
 738                 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
 739                         $multi = true;
 740                         $keys = array_keys( $a[0] );
 741                 } else {
 742                         $multi = false;
 743                         $keys = array_keys( $a );
 744                 }
 745
 746                 $sql = 'INSERT ' . implode( ' ', $options ) .
 747                         " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
 748
 749                 if ( $multi ) {
 750                         $first = true;
 751                         foreach ( $a as $row ) {
 752                                 if ( $first ) {
 753                                         $first = false;
 754                                 } else {
 755                                         $sql .= ',';
 756                                 }
 757                                 $sql .= '(' . $this->makeList( $row ) . ')';
 758                         }
 759                 } else {
 760                         $sql .= '(' . $this->makeList( $a ) . ')';
 761                 }
 762                 return !!$this->query( $sql, $fname );
 763         }
 764
 765         /**
 766          * @todo document
 767          */
 768         function updateArray( $table, $values, $conds, $fname = 'Database::updateArray' ) {
 769                 return $this->update( $table, $values, $conds, $fname );
 770         }
 771
 772         /**
 773          * UPDATE wrapper, takes a condition array and a SET array
 774          */
 775         function update( $table, $values, $conds, $fname = 'Database::update' ) {
 776                 $table = $this->tableName( $table );
 777                 $sql = "UPDATE $table SET " . $this->makeList( $values, LIST_SET );
 778                 $sql .= " WHERE " . $this->makeList( $conds, LIST_AND );
 779                 $this->query( $sql, $fname );
 780         }
 781
 782         /**
 783          * Makes a wfStrencoded list from an array
 784          * $mode: LIST_COMMA         - comma separated, no field names
 785          *        LIST_AND           - ANDed WHERE clause (without the WHERE)
 786          *        LIST_SET           - comma separated with field names, like a SET clause
 787          *        LIST_NAMES         - comma separated field names
 788          */
 789         function makeList( $a, $mode = LIST_COMMA ) {
 790                 if ( !is_array( $a ) ) {
 791                         wfDebugDieBacktrace( 'Database::makeList called with incorrect parameters' );
 792                 }
 793
 794                 $first = true;
 795                 $list = '';
 796                 foreach ( $a as $field => $value ) {
 797                         if ( !$first ) {
 798                                 if ( $mode == LIST_AND ) {
 799                                         $list .= ' AND ';
 800                                 } else {
 801                                         $list .= ',';
 802                                 }
 803                         } else {
 804                                 $first = false;
 805                         }
 806                         if ( $mode == LIST_AND && is_numeric( $field ) ) {
 807                                 $list .= "($value)";
 808                         } else {
 809                                 if ( $mode == LIST_AND || $mode == LIST_SET ) {
 810                                         $list .= $field.'=';
 811                                 }
 812                                 $list .= ($mode==LIST_NAMES?$value:$this->addQuotes( $value ));
 813                         }
 814                 }
 815                 return $list;
 816         }
 817
 818         /**
 819          * @todo document
 820          */
 821         function selectDB( $db ) {
 822                 $this->mDBname = $db;
 823                 return mysql_select_db( $db, $this->mConn );
 824         }
 825
 826         /**
 827          * @todo document
 828          */
 829         function startTimer( $timeout ) {
 830                 global $IP;
 831                 if( function_exists( 'mysql_thread_id' ) ) {
 832                         # This will kill the query if it's still running after $timeout seconds.
 833                         $tid = mysql_thread_id( $this->mConn );
 834                         exec( "php $IP/killthread.php $timeout $tid &>/dev/null &" );
 835                 }
 836         }
 837
 838         /**
 839          * Does nothing at all
 840          * @todo document
 841          */
 842         function stopTimer() { }
 843
 844         /**
 845          * @param string $name database table name
 846          * @todo document
 847          */
 848         function tableName( $name ) {
 849                 global $wgSharedDB;
 850                 if ( $this->mTablePrefix !== '' ) {
 851                         if ( strpos( '.', $name ) === false ) {
 852                                 $name = $this->mTablePrefix . $name;
 853                         }
 854                 }
 855                 if ( isset( $wgSharedDB ) && 'user' == $name ) {
 856                         $name = $wgSharedDB . '.' . $name;
 857                 }
 858                 return $name;
 859         }
 860
 861         /**
 862          * @todo document
 863          */
 864         function tableNames() {
 865                 $inArray = func_get_args();
 866                 $retVal = array();
 867                 foreach ( $inArray as $name ) {
 868                         $retVal[$name] = $this->tableName( $name );
 869                 }
 870                 return $retVal;
 871         }
 872
 873         /**
 874          * Wrapper for addslashes()
 875          * @param string $s String to be slashed.
 876          * @return string slashed string.
 877          */
 878         function strencode( $s ) {
 879                 return addslashes( $s );
 880         }
 881
 882         /**
 883          * If it's a string, adds quotes and backslashes
 884          * Otherwise returns as-is
 885          */
 886         function addQuotes( $s ) {
 887                 if ( is_null( $s ) ) {
 888                         $s = 'NULL';
 889                 } else {
 890                         # This will also quote numeric values. This should be harmless,
 891                         # and protects against weird problems that occur when they really
 892                         # _are_ strings such as article titles and string->number->string
 893                         # conversion is not 1:1.
 894                         $s = "'" . $this->strencode( $s ) . "'";
 895                 }
 896                 return $s;
 897         }
 898
 899         /**
 900          * Returns an appropriately quoted sequence value for inserting a new row.
 901          * MySQL has autoincrement fields, so this is just NULL. But the PostgreSQL
 902          * subclass will return an integer, and save the value for insertId()
 903          */
 904         function nextSequenceValue( $seqName ) {
 905                 return NULL;
 906         }
 907
 908         /**
 909          * USE INDEX clause
 910          * PostgreSQL doesn't have them and returns ""
 911          */
 912         function useIndexClause( $index ) {
 913                 return 'USE INDEX ('.$index.')';
 914         }
 915
 916         /**
 917          * REPLACE query wrapper
 918          * PostgreSQL simulates this with a DELETE followed by INSERT
 919          * $row is the row to insert, an associative array
 920          * $uniqueIndexes is an array of indexes. Each element may be either a
 921          * field name or an array of field names
 922          *
 923          * It may be more efficient to leave off unique indexes which are unlikely to collide.
 924          * However if you do this, you run the risk of encountering errors which wouldn't have
 925          * occurred in MySQL
 926          *
 927          * @todo migrate comment to phodocumentor format
 928          */
 929         function replace( $table, $uniqueIndexes, $rows, $fname = 'Database::replace' ) {
 930                 $table = $this->tableName( $table );
 931
 932                 # Single row case
 933                 if ( !is_array( reset( $rows ) ) ) {
 934                         $rows = array( $rows );
 935                 }
 936
 937                 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) .') VALUES ';
 938                 $first = true;
 939                 foreach ( $rows as $row ) {
 940                         if ( $first ) {
 941                                 $first = false;
 942                         } else {
 943                                 $sql .= ',';
 944                         }
 945                         $sql .= '(' . $this->makeList( $row ) . ')';
 946                 }
 947                 return $this->query( $sql, $fname );
 948         }
 949
 950         /**
 951          * DELETE where the condition is a join
 952          * MySQL does this with a multi-table DELETE syntax, PostgreSQL does it with sub-selects
 953          *
 954          * For safety, an empty $conds will not delete everything. If you want to delete all rows where the
 955          * join condition matches, set $conds='*'
 956          *
 957          * DO NOT put the join condition in $conds
 958          *
 959          * @param string $delTable The table to delete from.
 960          * @param string $joinTable The other table.
 961          * @param string $delVar The variable to join on, in the first table.
 962          * @param string $joinVar The variable to join on, in the second table.
 963          * @param array $conds Condition array of field names mapped to variables, ANDed together in the WHERE clause
 964          */
 965         function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = 'Database::deleteJoin' ) {
 966                 if ( !$conds ) {
 967                         wfDebugDieBacktrace( 'Database::deleteJoin() called with empty $conds' );
 968                 }
 969
 970                 $delTable = $this->tableName( $delTable );
 971                 $joinTable = $this->tableName( $joinTable );
 972                 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
 973                 if ( $conds != '*' ) {
 974                         $sql .= ' AND ' . $this->makeList( $conds, LIST_AND );
 975                 }
 976
 977                 return $this->query( $sql, $fname );
 978         }
 979
 980         /**
 981          * Returns the size of a text field, or -1 for "unlimited"
 982          */
 983         function textFieldSize( $table, $field ) {
 984                 $table = $this->tableName( $table );
 985                 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
 986                 $res = $this->query( $sql, 'Database::textFieldSize' );
 987                 $row = $this->fetchObject( $res );
 988                 $this->freeResult( $res );
 989
 990                 if ( preg_match( "/\((.*)\)/", $row->Type, $m ) ) {
 991                         $size = $m[1];
 992                 } else {
 993                         $size = -1;
 994                 }
 995                 return $size;
 996         }
 997
 998         /**
 999          * @return string Always return 'LOW_PRIORITY'
1000          */
1001         function lowPriorityOption() {
1002                 return 'LOW_PRIORITY';
1003         }
1004
1005         /**
1006          * Use $conds == "*" to delete all rows
1007          * @todo document
1008          */
1009         function delete( $table, $conds, $fname = 'Database::delete' ) {
1010                 if ( !$conds ) {
1011                         wfDebugDieBacktrace( 'Database::delete() called with no conditions' );
1012                 }
1013                 $table = $this->tableName( $table );
1014                 $sql = "DELETE FROM $table ";
1015                 if ( $conds != '*' ) {
1016                         $sql .= 'WHERE ' . $this->makeList( $conds, LIST_AND );
1017                 }
1018                 return $this->query( $sql, $fname );
1019         }
1020
1021         /**
1022          * INSERT SELECT wrapper
1023          * $varMap must be an associative array of the form array( 'dest1' => 'source1', ...)
1024          * Source items may be literals rather than field names, but strings should be quoted with Database::addQuotes()
1025          * $conds may be "*" to copy the whole table
1026          */
1027         function insertSelect( $destTable, $srcTable, $varMap, $conds, $fname = 'Database::insertSelect' ) {
1028                 $destTable = $this->tableName( $destTable );
1029                 $srcTable = $this->tableName( $srcTable );
1030                 $sql = "INSERT INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ')' .
1031                         ' SELECT ' . implode( ',', $varMap ) .
1032                         " FROM $srcTable";
1033                 if ( $conds != '*' ) {
1034                         $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND );
1035                 }
1036                 return $this->query( $sql, $fname );
1037         }
1038
1039         /**
1040          * @todo document
1041          */
1042         function limitResult($limit,$offset) {
1043                 return ' LIMIT '.(is_numeric($offset)?"{$offset},":"")."{$limit} ";
1044         }
1045
1046         /**
1047          * Returns an SQL expression for a simple conditional.
1048          * Uses IF on MySQL.
1049          *
1050          * @param string $cond SQL expression which will result in a boolean value
1051          * @param string $trueVal SQL expression to return if true
1052          * @param string $falseVal SQL expression to return if false
1053          * @return string SQL fragment
1054          */
1055         function conditional( $cond, $trueVal, $falseVal ) {
1056                 return " IF($cond, $trueVal, $falseVal) ";
1057         }
1058
1059         /**
1060          * @todo document
1061          */
1062         function wasDeadlock() {
1063                 return $this->lastErrno() == 1213;
1064         }
1065
1066         /**
1067          * @todo document
1068          */
1069         function deadlockLoop() {
1070                 $myFname = 'Database::deadlockLoop';
1071
1072                 $this->query( 'BEGIN', $myFname );
1073                 $args = func_get_args();
1074                 $function = array_shift( $args );
1075                 $oldIgnore = $dbw->ignoreErrors( true );
1076                 $tries = DEADLOCK_TRIES;
1077                 if ( is_array( $function ) ) {
1078                         $fname = $function[0];
1079                 } else {
1080                         $fname = $function;
1081                 }
1082                 do {
1083                         $retVal = call_user_func_array( $function, $args );
1084                         $error = $this->lastError();
1085                         $errno = $this->lastErrno();
1086                         $sql = $this->lastQuery();
1087
1088                         if ( $errno ) {
1089                                 if ( $dbw->wasDeadlock() ) {
1090                                         # Retry
1091                                         usleep( mt_rand( DEADLOCK_DELAY_MIN, DEADLOCK_DELAY_MAX ) );
1092                                 } else {
1093                                         $dbw->reportQueryError( $error, $errno, $sql, $fname );
1094                                 }
1095                         }
1096                 } while( $dbw->wasDeadlock && --$tries > 0 );
1097                 $this->ignoreErrors( $oldIgnore );
1098                 if ( $tries <= 0 ) {
1099                         $this->query( 'ROLLBACK', $myFname );
1100                         $this->reportQueryError( $error, $errno, $sql, $fname );
1101                         return false;
1102                 } else {
1103                         $this->query( 'COMMIT', $myFname );
1104                         return $retVal;
1105                 }
1106         }
1107
1108         /**
1109          * Do a SELECT MASTER_POS_WAIT()
1110          * @todo document
1111          */
1112         function masterPosWait( $file, $pos, $timeout ) {
1113                 $encFile = $this->strencode( $file );
1114                 $sql = "SELECT MASTER_POS_WAIT('$encFile', $pos, $timeout)";
1115                 $res = $this->query( $sql, 'Database::masterPosWait' );
1116                 if ( $res && $row = $this->fetchRow( $res ) ) {
1117                         $this->freeResult( $res );
1118                         return $row[0];
1119                 } else {
1120                         return false;
1121                 }
1122         }
1123
1124         /**
1125          * Get the position of the master from SHOW SLAVE STATUS
1126          */
1127         function getSlavePos() {
1128                 $res = $this->query( 'SHOW SLAVE STATUS', 'Database::getSlavePos' );
1129                 $row = $this->fetchObject( $res );
1130                 if ( $row ) {
1131                         return array( $row->Master_Log_File, $row->Read_Master_Log_Pos );
1132                 } else {
1133                         return array( false, false );
1134                 }
1135         }
1136
1137         /**
1138          * Get the position of the master from SHOW MASTER STATUS
1139          */
1140         function getMasterPos() {
1141                 $res = $this->query( 'SHOW MASTER STATUS', 'Database::getMasterPos' );
1142                 $row = $this->fetchObject( $res );
1143                 if ( $row ) {
1144                         return array( $row->File, $row->Position );
1145                 } else {
1146                         return array( false, false );
1147                 }
1148         }
1149
1150         /**
1151          * Begin a transaction, or if a transaction has already started, continue it
1152          */
1153         function begin( $fname = 'Database::begin' ) {
1154                 if ( !$this->mTrxLevel ) {
1155                         $this->immediateBegin( $fname );
1156                 } else {
1157                         $this->mTrxLevel++;
1158                 }
1159         }
1160
1161         /**
1162          * End a transaction, or decrement the nest level if transactions are nested
1163          */
1164         function commit( $fname = 'Database::commit' ) {
1165                 if ( $this->mTrxLevel ) {
1166                         $this->mTrxLevel--;
1167                 }
1168                 if ( !$this->mTrxLevel ) {
1169                         $this->immediateCommit( $fname );
1170                 }
1171         }
1172
1173         /**
1174          * Rollback a transaction
1175          */
1176         function rollback( $fname = 'Database::rollback' ) {
1177                 $this->query( 'ROLLBACK', $fname );
1178                 $this->mTrxLevel = 0;
1179         }
1180
1181         /**
1182          * Begin a transaction, committing any previously open transaction
1183          */
1184         function immediateBegin( $fname = 'Database::immediateBegin' ) {
1185                 $this->query( 'BEGIN', $fname );
1186                 $this->mTrxLevel = 1;
1187         }
1188
1189         /**
1190          * Commit transaction, if one is open
1191          */
1192         function immediateCommit( $fname = 'Database::immediateCommit' ) {
1193                 $this->query( 'COMMIT', $fname );
1194                 $this->mTrxLevel = 0;
1195         }
1196
1197         /**
1198          * Return MW-style timestamp used for MySQL schema
1199          */
1200         function timestamp( $ts=0 ) {
1201                 return wfTimestamp(TS_MW,$ts);
1202         }
1203
1204         /**
1205          * @todo document
1206          */
1207         function &resultObject( &$result ) {
1208                 if( empty( $result ) ) {
1209                         return NULL;
1210                 } else {
1211                         return new ResultWrapper( $this, $result );
1212                 }
1213         }
1214
1215         /**
1216          * Return aggregated value alias
1217          */
1218         function aggregateValue ($valuedata,$valuename='value') {
1219                 return $valuename;
1220         }
1221
1222         /**
1223          * @return string wikitext of a link to the server software's web site
1224          */
1225         function getSoftwareLink() {
1226                 return "[http://www.mysql.com/ MySQL]";
1227         }
1228
1229         /**
1230          * @return string Version information from the database
1231          */
1232         function getServerVersion() {
1233                 return mysql_get_server_info();
1234         }
1235 }
1236
1237 /**
1238  * Database abstraction object for mySQL
1239  * Inherit all methods and properties of Database::Database()
1240  *
1241  * @package MediaWiki
1242  * @see Database
1243  * @version # $Id$
1244  */
1245 class DatabaseMysql extends Database {
1246         # Inherit all
1247 }
1248
1249
1250 /**
1251  * Result wrapper for grabbing data queried by someone else
1252  *
1253  * @package MediaWiki
1254  * @version # $Id$
1255  */
1256 class ResultWrapper {
1257         var $db, $result;
1258
1259         /**
1260          * @todo document
1261          */
1262         function ResultWrapper( $database, $result ) {
1263                 $this->db =& $database;
1264                 $this->result =& $result;
1265         }
1266
1267         /**
1268          * @todo document
1269          */
1270         function numRows() {
1271                 return $this->db->numRows( $this->result );
1272         }
1273
1274         /**
1275          * @todo document
1276          */
1277         function &fetchObject() {
1278                 return $this->db->fetchObject( $this->result );
1279         }
1280
1281         /**
1282          * @todo document
1283          */
1284         function &fetchRow() {
1285                 return $this->db->fetchRow( $this->result );
1286         }
1287
1288         /**
1289          * @todo document
1290          */
1291         function free() {
1292                 $this->db->freeResult( $this->result );
1293                 unset( $this->result );
1294                 unset( $this->db );
1295         }
1296 }
1297
1298 #------------------------------------------------------------------------------
1299 # Global functions
1300 #------------------------------------------------------------------------------
1301
1302 /**
1303  * Standard fail function, called by default when a connection cannot be
1304  * established.
1305  * Displays the file cache if possible
1306  */
1307 function wfEmergencyAbort( &$conn, $error ) {
1308         global $wgTitle, $wgUseFileCache, $title, $wgInputEncoding, $wgSiteNotice, $wgOutputEncoding;
1309
1310         if( !headers_sent() ) {
1311                 header( 'HTTP/1.0 500 Internal Server Error' );
1312                 header( 'Content-type: text/html; charset='.$wgOutputEncoding );
1313                 /* Don't cache error pages!  They cause no end of trouble... */
1314                 header( 'Cache-control: none' );
1315                 header( 'Pragma: nocache' );
1316         }
1317         $msg = $wgSiteNotice;
1318         if($msg == '') $msg = wfMsgNoDB( 'noconnect', $error );
1319         $text = $msg;
1320
1321         if($wgUseFileCache) {
1322                 if($wgTitle) {
1323                         $t =& $wgTitle;
1324                 } else {
1325                         if($title) {
1326                                 $t = Title::newFromURL( $title );
1327                         } elseif (@/**/$_REQUEST['search']) {
1328                                 $search = $_REQUEST['search'];
1329                                 echo wfMsgNoDB( 'searchdisabled' );
1330                                 echo wfMsgNoDB( 'googlesearch', htmlspecialchars( $search ), $wgInputEncoding );
1331                                 wfErrorExit();
1332                         } else {
1333                                 $t = Title::newFromText( wfMsgNoDB( 'mainpage' ) );
1334                         }
1335                 }
1336
1337                 $cache = new CacheManager( $t );
1338                 if( $cache->isFileCached() ) {
1339                         $msg = '<p style="color: red"><b>'.$msg."<br />\n" .
1340                                 wfMsgNoDB( 'cachederror' ) . "</b></p>\n";
1341
1342                         $tag = '<div id="article">';
1343                         $text = str_replace(
1344                                 $tag,
1345                                 $tag . $msg,
1346                                 $cache->fetchPageText() );
1347                 }
1348         }
1349
1350         echo $text;
1351         wfErrorExit();
1352 }
1353
1354 ?>