mysqli.php

Aller à la documentation de ce fichier.

<?php
/**
 * @package     Joomla.Platform
 * @subpackage  Database
 *
 * @copyright   Copyright (C) 2005 - 2013 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE
 */

defined('JPATH_PLATFORM') or die;

/**
 * MySQLi database driver
 *
 * @package     Joomla.Platform
 * @subpackage  Database
 * @see         http://php.net/manual/en/book.mysqli.php
 * @since       12.1
 */
class JDatabaseDriverMysqli extends JDatabaseDriver
{
        /**
         * The name of the database driver.
         *
         * @var    string
         * @since  12.1
         */
        public $name = 'mysqli';

        /**
         * The character(s) used to quote SQL statement names such as table names or field names,
         * etc. The child classes should define this as necessary.  If a single character string the
         * same character is used for both sides of the quoted name, else the first character will be
         * used for the opening quote and the second for the closing quote.
         *
         * @var    string
         * @since  12.2
         */
        protected $nameQuote = '`';

        /**
         * The null or zero representation of a timestamp for the database driver.  This should be
         * defined in child classes to hold the appropriate value for the engine.
         *
         * @var    string
         * @since  12.2
         */
        protected $nullDate = '0000-00-00 00:00:00';

        /**
         * @var    string  The minimum supported database version.
         * @since  12.2
         */
        protected static $dbMinimum = '5.0.4';

        /**
         * Constructor.
         *
         * @param   array  $options  List of options used to configure the connection
         *
         * @since   12.1
         */
        public function __construct($options)
        {
                // Get some basic values from the options.
                $options['host'] = (isset($options['host'])) ? $options['host'] : 'localhost';
                $options['user'] = (isset($options['user'])) ? $options['user'] : 'root';
                $options['password'] = (isset($options['password'])) ? $options['password'] : '';
                $options['database'] = (isset($options['database'])) ? $options['database'] : '';
                $options['select'] = (isset($options['select'])) ? (bool) $options['select'] : true;
                $options['port'] = null;
                $options['socket'] = null;

                // Finalize initialisation.
                parent::__construct($options);
        }

        /**
         * Destructor.
         *
         * @since   12.1
         */
        public function __destruct()
        {
                $this->disconnect();
        }

        /**
         * Connects to the database if needed.
         *
         * @return  void  Returns void if the database connected successfully.
         *
         * @since   12.1
         * @throws  RuntimeException
         */
        public function connect()
        {
                if ($this->connection)
                {
                        return;
                }

                /*
                 * Unlike mysql_connect(), mysqli_connect() takes the port and socket as separate arguments. Therefore, we
                 * have to extract them from the host string.
                 */
                $port = isset($this->options['port']) ? $this->options['port'] : 3306;

                if (preg_match('/^(?P<host>((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?))(:(?P<port>.+))?$/', $this->options['host'], $matches))
                {
                        // It's an IPv4 address with ot without port
                        $this->options['host'] = $matches['host'];

                        if (!empty($matches['port']))
                        {
                                $port = $matches['port'];
                        }
                }
                elseif (preg_match('/^(?P<host>\[.*\])(:(?P<port>.+))?$/', $this->options['host'], $matches))
                {
                        // We assume square-bracketed IPv6 address with or without port, e.g. [fe80:102::2%eth1]:3306
                        $this->options['host'] = $matches['host'];

                        if (!empty($matches['port']))
                        {
                                $port = $matches['port'];
                        }
                }
                elseif (preg_match('/^(?P<host>(\w+:\/{2,3})?[a-z0-9\.\-]+)(:(?P<port>[^:]+))?$/i', $this->options['host'], $matches))
                {
                        // Named host (e.g domain.com or localhost) with ot without port
                        $this->options['host'] = $matches['host'];

                        if (!empty($matches['port']))
                        {
                                $port = $matches['port'];
                        }
                }
                elseif (preg_match('/^:(?P<port>[^:]+)$/', $this->options['host'], $matches))
                {
                        // Empty host, just port, e.g. ':3306'
                        $this->options['host'] = 'localhost';
                        $port = $matches['port'];
                }
                // ... else we assume normal (naked) IPv6 address, so host and port stay as they are or default

                // Get the port number or socket name
                if (is_numeric($port))
                {
                        $this->options['port'] = (int) $port;
                }
                else
                {
                        $this->options['socket'] = $port;
                }

                // Make sure the MySQLi extension for PHP is installed and enabled.
                if (!function_exists('mysqli_connect'))
                {
                        throw new RuntimeException('The MySQL adapter mysqli is not available');
                }

                $this->connection = @mysqli_connect(
                        $this->options['host'], $this->options['user'], $this->options['password'], null, $this->options['port'], $this->options['socket']
                );

                // Attempt to connect to the server.
                if (!$this->connection)
                {
                        throw new RuntimeException('Could not connect to MySQL.');
                }

                // Set sql_mode to non_strict mode
                mysqli_query($this->connection, "SET @@SESSION.sql_mode = '';");

                // If auto-select is enabled select the given database.
                if ($this->options['select'] && !empty($this->options['database']))
                {
                        $this->select($this->options['database']);
                }

                // Set charactersets (needed for MySQL 4.1.2+).
                $this->setUTF();

                // Turn MySQL profiling ON in debug mode:
                if ($this->debug && $this->hasProfiling())
                {
                        mysqli_query($this->connection, "SET profiling_history_size = 100;");
                        mysqli_query($this->connection, "SET profiling = 1;");
                }
        }

        /**
         * Disconnects the database.
         *
         * @return  void
         *
         * @since   12.1
         */
        public function disconnect()
        {
                // Close the connection.
                if ($this->connection)
                {
                        foreach ($this->disconnectHandlers as $h)
                        {
                                call_user_func_array($h, array( &$this));
                        }

                        mysqli_close($this->connection);
                }

                $this->connection = null;
        }

        /**
         * Method to escape a string for usage in an SQL statement.
         *
         * @param   string   $text   The string to be escaped.
         * @param   boolean  $extra  Optional parameter to provide extra escaping.
         *
         * @return  string  The escaped string.
         *
         * @since   12.1
         */
        public function escape($text, $extra = false)
        {
                $this->connect();

                $result = mysqli_real_escape_string($this->getConnection(), $text);

                if ($extra)
                {
                        $result = addcslashes($result, '%_');
                }

                return $result;
        }

        /**
         * Test to see if the MySQL connector is available.
         *
         * @return  boolean  True on success, false otherwise.
         *
         * @since   12.1
         */
        public static function isSupported()
        {
                return (function_exists('mysqli_connect'));
        }

        /**
         * Determines if the connection to the server is active.
         *
         * @return  boolean  True if connected to the database engine.
         *
         * @since   12.1
         */
        public function connected()
        {
                if (is_object($this->connection))
                {
                        return mysqli_ping($this->connection);
                }

                return false;
        }

        /**
         * Drops a table from the database.
         *
         * @param   string   $tableName  The name of the database table to drop.
         * @param   boolean  $ifExists   Optionally specify that the table must exist before it is dropped.
         *
         * @return  JDatabaseDriverMysqli  Returns this object to support chaining.
         *
         * @since   12.2
         * @throws  RuntimeException
         */
        public function dropTable($tableName, $ifExists = true)
        {
                $this->connect();

                $query = $this->getQuery(true);

                $this->setQuery('DROP TABLE ' . ($ifExists ? 'IF EXISTS ' : '') . $query->quoteName($tableName));

                $this->execute();

                return $this;
        }

        /**
         * Get the number of affected rows for the previous executed SQL statement.
         *
         * @return  integer  The number of affected rows.
         *
         * @since   12.1
         */
        public function getAffectedRows()
        {
                $this->connect();

                return mysqli_affected_rows($this->connection);
        }

        /**
         * Method to get the database collation in use by sampling a text field of a table in the database.
         *
         * @return  mixed  The collation in use by the database (string) or boolean false if not supported.
         *
         * @since   12.2
         * @throws  RuntimeException
         */
        public function getCollation()
        {
                $this->connect();

                $tables = $this->getTableList();

                $this->setQuery('SHOW FULL COLUMNS FROM ' . $tables[0]);
                $array = $this->loadAssocList();

                foreach ($array as $field)
                {
                        if (!is_null($field['Collation']))
                        {
                                return $field['Collation'];
                        }
                }

                return null;
        }

        /**
         * Get the number of returned rows for the previous executed SQL statement.
         *
         * @param   resource  $cursor  An optional database cursor resource to extract the row count from.
         *
         * @return  integer   The number of returned rows.
         *
         * @since   12.1
         */
        public function getNumRows($cursor = null)
        {
                return mysqli_num_rows($cursor ? $cursor : $this->cursor);
        }

        /**
         * Shows the table CREATE statement that creates the given tables.
         *
         * @param   mixed  $tables  A table name or a list of table names.
         *
         * @return  array  A list of the create SQL for the tables.
         *
         * @since   12.1
         * @throws  RuntimeException
         */
        public function getTableCreate($tables)
        {
                $this->connect();

                $result = array();

                // Sanitize input to an array and iterate over the list.
                settype($tables, 'array');
                foreach ($tables as $table)
                {
                        // Set the query to get the table CREATE statement.
                        $this->setQuery('SHOW CREATE table ' . $this->quoteName($this->escape($table)));
                        $row = $this->loadRow();

                        // Populate the result array based on the create statements.
                        $result[$table] = $row[1];
                }

                return $result;
        }

        /**
         * Retrieves field information about a given table.
         *
         * @param   string   $table     The name of the database table.
         * @param   boolean  $typeOnly  True to only return field types.
         *
         * @return  array  An array of fields for the database table.
         *
         * @since   12.2
         * @throws  RuntimeException
         */
        public function getTableColumns($table, $typeOnly = true)
        {
                $this->connect();

                $result = array();

                // Set the query to get the table fields statement.
                $this->setQuery('SHOW FULL COLUMNS FROM ' . $this->quoteName($this->escape($table)));
                $fields = $this->loadObjectList();

                // If we only want the type as the value add just that to the list.
                if ($typeOnly)
                {
                        foreach ($fields as $field)
                        {
                                $result[$field->Field] = preg_replace("/[(0-9)]/", '', $field->Type);
                        }
                }
                // If we want the whole field data object add that to the list.
                else
                {
                        foreach ($fields as $field)
                        {
                                $result[$field->Field] = $field;
                        }
                }

                return $result;
        }

        /**
         * Get the details list of keys for a table.
         *
         * @param   string  $table  The name of the table.
         *
         * @return  array  An array of the column specification for the table.
         *
         * @since   12.2
         * @throws  RuntimeException
         */
        public function getTableKeys($table)
        {
                $this->connect();

                // Get the details columns information.
                $this->setQuery('SHOW KEYS FROM ' . $this->quoteName($table));
                $keys = $this->loadObjectList();

                return $keys;
        }

        /**
         * Method to get an array of all tables in the database.
         *
         * @return  array  An array of all the tables in the database.
         *
         * @since   12.2
         * @throws  RuntimeException
         */
        public function getTableList()
        {
                $this->connect();

                // Set the query to get the tables statement.
                $this->setQuery('SHOW TABLES');
                $tables = $this->loadColumn();

                return $tables;
        }

        /**
         * Get the version of the database connector.
         *
         * @return  string  The database connector version.
         *
         * @since   12.1
         */
        public function getVersion()
        {
                $this->connect();

                return mysqli_get_server_info($this->connection);
        }

        /**
         * Method to get the auto-incremented value from the last INSERT statement.
         *
         * @return  mixed  The value of the auto-increment field from the last inserted row.
         *                 If the value is greater than maximal int value, it will return a string.
         *
         * @since   12.1
         */
        public function insertid()
        {
                $this->connect();

                return mysqli_insert_id($this->connection);
        }

        /**
         * Locks a table in the database.
         *
         * @param   string  $table  The name of the table to unlock.
         *
         * @return  JDatabaseDriverMysqli  Returns this object to support chaining.
         *
         * @since   12.2
         * @throws  RuntimeException
         */
        public function lockTable($table)
        {
                $this->setQuery('LOCK TABLES ' . $this->quoteName($table) . ' WRITE')->execute();

                return $this;
        }

        /**
         * Execute the SQL statement.
         *
         * @return  mixed  A database cursor resource on success, boolean false on failure.
         *
         * @since   12.1
         * @throws  RuntimeException
         */
        public function execute()
        {
                $this->connect();

                if (!is_object($this->connection))
                {
                        JLog::add(JText::sprintf('JLIB_DATABASE_QUERY_FAILED', $this->errorNum, $this->errorMsg), JLog::ERROR, 'database');
                        throw new RuntimeException($this->errorMsg, $this->errorNum);
                }

                // Take a local copy so that we don't modify the original query and cause issues later
                $query = $this->replacePrefix((string) $this->sql);

                if (!($this->sql instanceof JDatabaseQuery) && ($this->limit > 0 || $this->offset > 0))
                {
                        $query .= ' LIMIT ' . $this->offset . ', ' . $this->limit;
                }

                // Increment the query counter.
                $this->count++;

                // Reset the error values.
                $this->errorNum = 0;
                $this->errorMsg = '';
                $memoryBefore = null;

                // If debugging is enabled then let's log the query.
                if ($this->debug)
                {
                        // Add the query to the object queue.
                        $this->log[] = $query;

                        JLog::add($query, JLog::DEBUG, 'databasequery');

                        $this->timings[] = microtime(true);

                        if (is_object($this->cursor))
                        {
                                // Avoid warning if result already freed by third-party library
                                @$this->freeResult();
                        }
                        $memoryBefore = memory_get_usage();
                }

                // Execute the query. Error suppression is used here to prevent warnings/notices that the connection has been lost.
                $this->cursor = @mysqli_query($this->connection, $query);

                if ($this->debug)
                {
                        $this->timings[] = microtime(true);
                        if (defined('DEBUG_BACKTRACE_IGNORE_ARGS'))
                        {
                                $this->callStacks[] = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
                        }
                        else
                        {
                                $this->callStacks[] = debug_backtrace();
                        }
                        $this->callStacks[count($this->callStacks) - 1][0]['memory'] = array($memoryBefore, memory_get_usage(), is_object($this->cursor) ? $this->getNumRows() : null);
                }

                // If an error occurred handle it.
                if (!$this->cursor)
                {
                        $this->errorNum = (int) mysqli_errno($this->connection);
                        $this->errorMsg = (string) mysqli_error($this->connection) . ' SQL=' . $query;

                        // Check if the server was disconnected.
                        if (!$this->connected())
                        {
                                try
                                {
                                        // Attempt to reconnect.
                                        $this->connection = null;
                                        $this->connect();
                                }
                                // If connect fails, ignore that exception and throw the normal exception.
                                catch (RuntimeException $e)
                                {
                                        JLog::add(JText::sprintf('JLIB_DATABASE_QUERY_FAILED', $this->errorNum, $this->errorMsg), JLog::ERROR, 'databasequery');
                                        throw new RuntimeException($this->errorMsg, $this->errorNum);
                                }

                                // Since we were able to reconnect, run the query again.
                                return $this->execute();
                        }
                        // The server was not disconnected.
                        else
                        {
                                JLog::add(JText::sprintf('JLIB_DATABASE_QUERY_FAILED', $this->errorNum, $this->errorMsg), JLog::ERROR, 'databasequery');
                                throw new RuntimeException($this->errorMsg, $this->errorNum);
                        }
                }

                return $this->cursor;
        }

        /**
         * Renames a table in the database.
         *
         * @param   string  $oldTable  The name of the table to be renamed
         * @param   string  $newTable  The new name for the table.
         * @param   string  $backup    Not used by MySQL.
         * @param   string  $prefix    Not used by MySQL.
         *
         * @return  JDatabaseDriverMysqli  Returns this object to support chaining.
         *
         * @since   12.2
         * @throws  RuntimeException
         */
        public function renameTable($oldTable, $newTable, $backup = null, $prefix = null)
        {
                $this->setQuery('RENAME TABLE ' . $oldTable . ' TO ' . $newTable)->execute();

                return $this;
        }

        /**
         * Select a database for use.
         *
         * @param   string  $database  The name of the database to select for use.
         *
         * @return  boolean  True if the database was successfully selected.
         *
         * @since   12.1
         * @throws  RuntimeException
         */
        public function select($database)
        {
                $this->connect();

                if (!$database)
                {
                        return false;
                }

                if (!mysqli_select_db($this->connection, $database))
                {
                        throw new RuntimeException('Could not connect to database.');
                }

                return true;
        }

        /**
         * Set the connection to use UTF-8 character encoding.
         *
         * @return  boolean  True on success.
         *
         * @since   12.1
         */
        public function setUTF()
        {
                $this->connect();

                return $this->connection->set_charset('utf8');
        }

        /**
         * Method to commit a transaction.
         *
         * @param   boolean  $toSavepoint  If true, commit to the last savepoint.
         *
         * @return  void
         *
         * @since   12.2
         * @throws  RuntimeException
         */
        public function transactionCommit($toSavepoint = false)
        {
                $this->connect();

                if (!$toSavepoint || $this->transactionDepth <= 1)
                {
                        if ($this->setQuery('COMMIT')->execute())
                        {
                                $this->transactionDepth = 0;
                        }

                        return;
                }

                $this->transactionDepth--;
        }

        /**
         * Method to roll back a transaction.
         *
         * @param   boolean  $toSavepoint  If true, rollback to the last savepoint.
         *
         * @return  void
         *
         * @since   12.2
         * @throws  RuntimeException
         */
        public function transactionRollback($toSavepoint = false)
        {
                $this->connect();

                if (!$toSavepoint || $this->transactionDepth <= 1)
                {
                        if ($this->setQuery('ROLLBACK')->execute())
                        {
                                $this->transactionDepth = 0;
                        }

                        return;
                }

                $savepoint = 'SP_' . ($this->transactionDepth - 1);
                $this->setQuery('ROLLBACK TO SAVEPOINT ' . $this->quoteName($savepoint));

                if ($this->execute())
                {
                        $this->transactionDepth--;
                }
        }

        /**
         * Method to initialize a transaction.
         *
         * @param   boolean  $asSavepoint  If true and a transaction is already active, a savepoint will be created.
         *
         * @return  void
         *
         * @since   12.2
         * @throws  RuntimeException
         */
        public function transactionStart($asSavepoint = false)
        {
                $this->connect();

                if (!$asSavepoint || !$this->transactionDepth)
                {
                        if ($this->setQuery('START TRANSACTION')->execute())
                        {
                                $this->transactionDepth = 1;
                        }

                        return;
                }

                $savepoint = 'SP_' . $this->transactionDepth;
                $this->setQuery('SAVEPOINT ' . $this->quoteName($savepoint));

                if ($this->execute())
                {
                        $this->transactionDepth++;
                }
        }

        /**
         * Method to fetch a row from the result set cursor as an array.
         *
         * @param   mixed  $cursor  The optional result set cursor from which to fetch the row.
         *
         * @return  mixed  Either the next row from the result set or false if there are no more rows.
         *
         * @since   12.1
         */
        protected function fetchArray($cursor = null)
        {
                return mysqli_fetch_row($cursor ? $cursor : $this->cursor);
        }

        /**
         * Method to fetch a row from the result set cursor as an associative array.
         *
         * @param   mixed  $cursor  The optional result set cursor from which to fetch the row.
         *
         * @return  mixed  Either the next row from the result set or false if there are no more rows.
         *
         * @since   12.1
         */
        protected function fetchAssoc($cursor = null)
        {
                return mysqli_fetch_assoc($cursor ? $cursor : $this->cursor);
        }

        /**
         * Method to fetch a row from the result set cursor as an object.
         *
         * @param   mixed   $cursor  The optional result set cursor from which to fetch the row.
         * @param   string  $class   The class name to use for the returned row object.
         *
         * @return  mixed   Either the next row from the result set or false if there are no more rows.
         *
         * @since   12.1
         */
        protected function fetchObject($cursor = null, $class = 'stdClass')
        {
                return mysqli_fetch_object($cursor ? $cursor : $this->cursor, $class);
        }

        /**
         * Method to free up the memory used for the result set.
         *
         * @param   mixed  $cursor  The optional result set cursor from which to fetch the row.
         *
         * @return  void
         *
         * @since   12.1
         */
        protected function freeResult($cursor = null)
        {
                mysqli_free_result($cursor ? $cursor : $this->cursor);
                if ((! $cursor) || ($cursor === $this->cursor))
                {
                        $this->cursor = null;
                }
        }

        /**
         * Unlocks tables in the database.
         *
         * @return  JDatabaseDriverMysqli  Returns this object to support chaining.
         *
         * @since   12.1
         * @throws  RuntimeException
         */
        public function unlockTables()
        {
                $this->setQuery('UNLOCK TABLES')->execute();

                return $this;
        }

        /**
         * Internal function to check if profiling is available
         *
         * @return  boolean
         *
         * @since 3.1.3
         */
        private function hasProfiling()
        {
                try
                {
                        $res = mysqli_query($this->connection, "SHOW VARIABLES LIKE 'have_profiling'");
                        $row = mysqli_fetch_assoc($res);

                        return isset($row);
                }
                catch (Exception $e)
                {
                        return false;
                }
        }
}