database.php

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		if( $wgDBmysql5 ) {
			// Tell the server we're communicating with it in UTF-8.
			// This may engage various charset conversions.
			$this->query( 'SET NAMES utf8' );
		}

		$this->mOpened = $success;
		return $success;
	}
	/**@}}*/

	/**
	 * Closes a database connection.
	 * if it is open : commits any open transactions
	 *
	 * @return bool operation success. true if already closed.
	 */
	function close()
	{
		$this->mOpened = false;
		if ( $this->mConn ) {
			if ( $this->trxLevel() ) {
				$this->immediateCommit();
			}
			return mysql_close( $this->mConn );
		} else {
			return true;
		}
	}

	/**
	 * @param string $error fallback error message, used if none is given by MySQL
	 */
	function reportConnectionError( $error = 'Unknown error' ) {
		$myError = $this->lastError();
		if ( $myError ) {
			$error = $myError;
		}

		if ( $this->mFailFunction ) {
			# Legacy error handling method
			if ( !is_int( $this->mFailFunction ) ) {
				$ff = $this->mFailFunction;
				$ff( $this, $error );
			}
		} else {
			# New method
			wfLogDBError( "Connection error: $error\n" );
			throw new DBConnectionError( $this, $error );
		}
	}

	/**
	 * Usually aborts on failure
	 * If errors are explicitly ignored, returns success
	 */
	function query( $sql, $fname = '', $tempIgnore = false ) {
		global $wgProfiling;

		if ( $wgProfiling ) {
			# generalizeSQL will probably cut down the query to reasonable
			# logging size most of the time. The substr is really just a sanity check.

			# Who's been wasting my precious column space? -- TS
			#$profName = 'query: ' . $fname . ' ' . substr( Database::generalizeSQL( $sql ), 0, 255 );

			if ( is_null( $this->getLBInfo( 'master' ) ) ) {
				$queryProf = 'query: ' . substr( mwDatabase::generalizeSQL( $sql ), 0, 255 );
				$totalProf = 'mwDatabase::query';
			} else {
				$queryProf = 'query-m: ' . substr( mwDatabase::generalizeSQL( $sql ), 0, 255 );
				$totalProf = 'mwDatabase::query-master';
			}
			wfProfileIn( $totalProf );
			wfProfileIn( $queryProf );
		}

		$this->mLastQuery = $sql;

		# Add a comment for easy SHOW PROCESSLIST interpretation
		if ( $fname ) {
			$commentedSql = preg_replace("/\s/", " /* $fname */ ", $sql, 1);
		} else {
			$commentedSql = $sql;
		}

		# If DBO_TRX is set, start a transaction
		if ( ( $this->mFlags & DBO_TRX ) && !$this->trxLevel() && 
			$sql != 'BEGIN' && $sql != 'COMMIT' && $sql != 'ROLLBACK' 
		) {
			$this->begin();
		}

		if ( $this->debug() ) {
			$sqlx = substr( $commentedSql, 0, 500 );
			$sqlx = strtr( $sqlx, "\t\n", '  ' );
			wfDebug( "SQL: $sqlx\n" );
		}

		# Do the query and handle errors
		$ret = $this->doQuery( $commentedSql );

		# Try reconnecting if the connection was lost
		if ( false === $ret && ( $this->lastErrno() == 2013 || $this->lastErrno() == 2006 ) ) {
			# Transaction is gone, like it or not
			$this->mTrxLevel = 0;
			wfDebug( "Connection lost, reconnecting...\n" );
			if ( $this->ping() ) {
				wfDebug( "Reconnected\n" );
				$ret = $this->doQuery( $commentedSql );
			} else {
				wfDebug( "Failed\n" );
			}
		}

		if ( false === $ret ) {
			$this->reportQueryError( $this->lastError(), $this->lastErrno(), $sql, $fname, $tempIgnore );
		}

		if ( $wgProfiling ) {
			wfProfileOut( $queryProf );
			wfProfileOut( $totalProf );
		}
		return $ret;
	}

	/**
	 * The DBMS-dependent part of query()
	 * @param string $sql SQL query.
	 */
	function doQuery( $sql ) {
		if( $this->bufferResults() ) {
			$ret = mysql_query( $sql, $this->mConn );
		} else {
			$ret = mysql_unbuffered_query( $sql, $this->mConn );
		}
		return $ret;
	}

	/**
	 * @param $error
	 * @param $errno
	 * @param $sql
	 * @param string $fname
	 * @param bool $tempIgnore
	 */
	function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
		global $wgCommandLineMode, $wgFullyInitialised, $wgColorErrors;
		# Ignore errors during error handling to avoid infinite recursion
		$ignore = $this->ignoreErrors( true );
		++$this->mErrorCount;

		if( $ignore || $tempIgnore ) {
			wfDebug("SQL ERROR (ignored): $error\n");
			$this->ignoreErrors( $ignore );
		} else {
			$sql1line = str_replace( "\n", "\\n", $sql );
			wfLogDBError("$fname\t{$this->mServer}\t$errno\t$error\t$sql1line\n");
			wfDebug("SQL ERROR: " . $error . "\n");
			throw new DBQueryError( $this, $error, $errno, $sql, $fname );
		}
	}


	/**
	 * Intended to be compatible with the PEAR::DB wrapper functions.
	 * http://pear.php.net/manual/en/package.database.db.intro-execute.php
	 *
	 * ? = scalar value, quoted as necessary
	 * ! = raw SQL bit (a function for instance)
	 * & = filename; reads the file and inserts as a blob
	 *     (we don't use this though...)
	 */
	function prepare( $sql, $func = 'mwDatabase::prepare' ) {
		/* MySQL doesn't support prepared statements (yet), so just
		   pack up the query for reference. We'll manually replace
		   the bits later. */
		return array( 'query' => $sql, 'func' => $func );
	}

	function freePrepared( $prepared ) {
		/* No-op for MySQL */
	}

	/**
	 * Execute a prepared query with the various arguments
	 * @param string $prepared the prepared sql
	 * @param mixed $args Either an array here, or put scalars as varargs
	 */
	function execute( $prepared, $args = null ) {
		if( !is_array( $args ) ) {
			# Pull the var args
			$args = func_get_args();
			array_shift( $args );
		}
		$sql = $this->fillPrepared( $prepared['query'], $args );
		return $this->query( $sql, $prepared['func'] );
	}

	/**
	 * Prepare & execute an SQL statement, quoting and inserting arguments
	 * in the appropriate places.
	 * @param string $query
	 * @param string $args ...
	 */
	function safeQuery( $query, $args = null ) {
		$prepared = $this->prepare( $query, 'mwDatabase::safeQuery' );
		if( !is_array( $args ) ) {
			# Pull the var args
			$args = func_get_args();
			array_shift( $args );
		}
		$retval = $this->execute( $prepared, $args );
		$this->freePrepared( $prepared );
		return $retval;
	}

	/**
	 * For faking prepared SQL statements on DBs that don't support
	 * it directly.
	 * @param string $preparedSql - a 'preparable' SQL statement
	 * @param array $args - array of arguments to fill it with
	 * @return string executable SQL
	 */
	function fillPrepared( $preparedQuery, $args ) {
		reset( $args );
		$this->preparedArgs =& $args;
		return preg_replace_callback( '/(\\\\[?!&]|[?!&])/',
			array( &$this, 'fillPreparedArg' ), $preparedQuery );
	}

	/**
	 * preg_callback func for fillPrepared()
	 * The arguments should be in $this->preparedArgs and must not be touched
	 * while we're doing this.
	 *
	 * @param array $matches
	 * @return string
	 * @private
	 */
	function fillPreparedArg( $matches ) {
		switch( $matches[1] ) {
			case '\\?': return '?';
			case '\\!': return '!';
			case '\\&': return '&';
		}
		list( $n, $arg ) = each( $this->preparedArgs );
		switch( $matches[1] ) {
			case '?': return $this->addQuotes( $arg );
			case '!': return $arg;
			case '&':
				# return $this->addQuotes( file_get_contents( $arg ) );
				throw new DBUnexpectedError( $this, '& mode is not implemented. If it\'s really needed, uncomment the line above.' );
			default:
				throw new DBUnexpectedError( $this, 'Received invalid match. This should never happen!' );
		}
	}

	/**#@+
	 * @param mixed $res A SQL result
	 */
	/**
	 * Free a result object
	 */
	function freeResult( $res ) {
		if ( !@/**/mysql_free_result( $res ) ) {
			throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
		}
	}

	/**
	 * Fetch the next row from the given result object, in object form
	 */
	function fetchObject( $res ) {
		@/**/$row = mysql_fetch_object( $res );
		if( mysql_errno() ) {
			throw new DBUnexpectedError( $this, 'Error in fetchObject(): ' . htmlspecialchars( mysql_error() ) );
		}
		return $row;
	}

	/**
	 * Fetch the next row from the given result object
	 * Returns an array
	 */
 	function fetchRow( $res ) {
		@/**/$row = mysql_fetch_array( $res );
		if (mysql_errno() ) {
			throw new DBUnexpectedError( $this, 'Error in fetchRow(): ' . htmlspecialchars( mysql_error() ) );
		}
		return $row;
	}

	/**
	 * Get the number of rows in a result object
	 */
	function numRows( $res ) {
		@/**/$n = mysql_num_rows( $res );
		if( mysql_errno() ) {
			throw new DBUnexpectedError( $this, 'Error in numRows(): ' . htmlspecialchars( mysql_error() ) );
		}
		return $n;
	}

	/**
	 * Get the number of fields in a result object
	 * See documentation for mysql_num_fields()
	 */
	function numFields( $res ) { return mysql_num_fields( $res ); }

	/**
	 * Get a field name in a result object
	 * See documentation for mysql_field_name():
	 * http://www.php.net/mysql_field_name
	 */
	function fieldName( $res, $n ) { return mysql_field_name( $res, $n ); }

	/**
	 * Get the inserted value of an auto-increment row
	 *
	 * The value inserted should be fetched from nextSequenceValue()
	 *
	 * Example:
	 * $id = $dbw->nextSequenceValue('page_page_id_seq');
	 * $dbw->insert('page',array('page_id' => $id));
	 * $id = $dbw->insertId();
	 */
	function insertId() { return mysql_insert_id( $this->mConn ); }

	/**
	 * Change the position of the cursor in a result object
	 * See mysql_data_seek()
	 */
	function dataSeek( $res, $row ) { return mysql_data_seek( $res, $row ); }

	/**
	 * Get the last error number
	 * See mysql_errno()
	 */
	function lastErrno() {
		if ( $this->mConn ) {
			return mysql_errno( $this->mConn );
		} else {
			return mysql_errno();
		}
	}

	/**
	 * Get a description of the last error
	 * See mysql_error() for more details
	 */
	function lastError() {
		if ( $this->mConn ) {
			# Even if it's non-zero, it can still be invalid
			wfSuppressWarnings();
			$error = mysql_error( $this->mConn );
			if ( !$error ) {
				$error = mysql_error();
			}
			wfRestoreWarnings();
		} else {
			$error = mysql_error();
		}
		if( $error ) {
			$error .= ' (' . $this->mServer . ')';
		}
		return $error;
	}
	/**
	 * Get the number of rows affected by the last write query
	 * See mysql_affected_rows() for more details
	 */
	function affectedRows() { return mysql_affected_rows( $this->mConn ); }
	/**#@-*/ // end of template : @param $result

	/**
	 * Simple UPDATE wrapper
	 * Usually aborts on failure
	 * If errors are explicitly ignored, returns success
	 *
	 * This function exists for historical reasons, Database::update() has a more standard
	 * calling convention and feature set
	 */
	function set( $table, $var, $value, $cond, $fname = 'mwDatabase::set' )
	{
		$table = $this->tableName( $table );
		$sql = "UPDATE $table SET $var = '" .
		  $this->strencode( $value ) . "' WHERE ($cond)";
		return (bool)$this->query( $sql, $fname );
	}

	/**
	 * Simple SELECT wrapper, returns a single field, input must be encoded
	 * Usually aborts on failure
	 * If errors are explicitly ignored, returns FALSE on failure
	 */
	function selectField( $table, $var, $cond='', $fname = 'mwDatabase::selectField', $options = array() ) {
		if ( !is_array( $options ) ) {
			$options = array( $options );
		}
		$options['LIMIT'] = 1;

		$res = $this->select( $table, $var, $cond, $fname, $options );
		if ( $res === false || !$this->numRows( $res ) ) {
			return false;
		}
		$row = $this->fetchRow( $res );
		if ( $row !== false ) {
			$this->freeResult( $res );
			return $row[0];
		} else {
			return false;
		}
	}

	/**
	 * Returns an optional USE INDEX clause to go after the table, and a
	 * string to go at the end of the query
	 *
	 * @private
	 *
	 * @param array $options an associative array of options to be turned into
	 *              an SQL query, valid keys are listed in the function.
	 * @return array
	 */
	function makeSelectOptions( $options ) {
		$tailOpts = '';
		$startOpts = '';

		$noKeyOptions = array();
		foreach ( $options as $key => $option ) {
			if ( is_numeric( $key ) ) {
				$noKeyOptions[$option] = true;
			}
		}

		if ( isset( $options['GROUP BY'] ) ) $tailOpts .= " GROUP BY {$options['GROUP BY']}";
		if ( isset( $options['ORDER BY'] ) ) $tailOpts .= " ORDER BY {$options['ORDER BY']}";
		
		if (isset($options['LIMIT'])) {
			$tailOpts .= $this->limitResult('', $options['LIMIT'],
				isset($options['OFFSET']) ? $options['OFFSET'] : false);
		}

		if ( isset( $noKeyOptions['FOR UPDATE'] ) ) $tailOpts .= ' FOR UPDATE';
		if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) $tailOpts .= ' LOCK IN SHARE MODE';
		if ( isset( $noKeyOptions['DISTINCT'] ) && isset( $noKeyOptions['DISTINCTROW'] ) ) $startOpts .= 'DISTINCT';

		# Various MySQL extensions
		if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) $startOpts .= ' HIGH_PRIORITY';
		if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) $startOpts .= ' SQL_BIG_RESULT';
		if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) $startOpts .= ' SQL_BUFFER_RESULT';
		if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) $startOpts .= ' SQL_SMALL_RESULT';
		if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) $startOpts .= ' SQL_CALC_FOUND_ROWS';
		if ( isset( $noKeyOptions['SQL_CACHE'] ) ) $startOpts .= ' SQL_CACHE';
		if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) $startOpts .= ' SQL_NO_CACHE';

		if ( isset( $options['USE INDEX'] ) && ! is_array( $options['USE INDEX'] ) ) {
			$useIndex = $this->useIndexClause( $options['USE INDEX'] );
		} else {
			$useIndex = '';
		}
		
		return array( $startOpts, $useIndex, $tailOpts );
	}

	/**
	 * SELECT wrapper
	 */
	function select( $table, $vars, $conds='', $fname = 'mwDatabase::select', $options = array() )
	{
		if( is_array( $vars ) ) {
			$vars = implode( ',', $vars );
		}
		if( !is_array( $options ) ) {
			$options = array( $options );
		}
		if( is_array( $table ) ) {
			if ( @is_array( $options['USE INDEX'] ) )
				$from = ' FROM ' . $this->tableNamesWithUseIndex( $table, $options['USE INDEX'] );
			else
				$from = ' FROM ' . implode( ',', array_map( array( &$this, 'tableName' ), $table ) );
		} elseif ($table!='') {
			$from = ' FROM ' . $this->tableName( $table );
		} else {
			$from = '';
		}

		list( $startOpts, $useIndex, $tailOpts ) = $this->makeSelectOptions( $options );

		if( !empty( $conds ) ) {
			if ( is_array( $conds ) ) {
				$conds = $this->makeList( $conds, LIST_AND );
			}
			$sql = "SELECT $startOpts $vars $from $useIndex WHERE $conds $tailOpts";
		} else {
			$sql = "SELECT $startOpts $vars $from $useIndex $tailOpts";
		}

		return $this->query( $sql, $fname );
	}

	/**
	 * Single row SELECT wrapper
	 * Aborts or returns FALSE on error
	 *
	 * $vars: the selected variables
	 * $conds: a condition map, terms are ANDed together.
	 *   Items with numeric keys are taken to be literal conditions
	 * Takes an array of selected variables, and a condition map, which is ANDed
	 * e.g: selectRow( "page", array( "page_id" ), array( "page_namespace" =>
	 * NS_MAIN, "page_title" => "Astronomy" ) )   would return an object where