Ticket #6305: wp-db.php

<?php
//  WordPress DB Class

//  ORIGINAL CODE FROM:
//  Justin Vincent (justin@visunet.ie)
//      http://php.justinvincent.com

define('EZSQL_VERSION', 'WP1.25');
define('OBJECT', 'OBJECT', true);
define('OBJECT_K', 'OBJECT_K', false);
define('ARRAY_A', 'ARRAY_A', false);
define('ARRAY_N', 'ARRAY_N', false);

if (!defined('SAVEQUERIES'))
        define('SAVEQUERIES', false);

class wpdb {

        var $show_errors = false;
        var $suppress_errors = false;
        var $last_error = '';
        var $num_queries = 0;
        var $last_query;
        var $col_info;
        var $queries;
        var $prefix = '';
        var $ready = false;

        // Our tables
        var $posts;
        var $users;
        var $categories;
        var $post2cat;
        var $comments;
        var $links;
        var $options;
        var $postmeta;
        var $usermeta;
        var $terms;
        var $term_taxonomy;
        var $term_relationships;
        var $tables = array('users', 'usermeta', 'posts', 'categories', 'post2cat', 'comments', 'links', 'link2cat', 'options',
                        'postmeta', 'terms', 'term_taxonomy', 'term_relationships');
        var $charset;
        var $collate;
        var $db_user;
        var $db_password;
        var $db_name;
        var $db_host;

        /**
         * Connects to the database server and selects a database
         * @param string $dbuser
         * @param string $dbpassword
         * @param string $dbname
         * @param string $dbhost
         */
        function wpdb($dbuser, $dbpassword, $dbname, $dbhost) {
                return $this->__construct($dbuser, $dbpassword, $dbname, $dbhost);
        }

        function __construct($dbuser, $dbpassword, $dbname, $dbhost) {
                register_shutdown_function(array(&$this, "__destruct"));

                if ( defined('WP_DEBUG') and WP_DEBUG == true )
                        $this->show_errors();

                if ( defined('DB_CHARSET') )
                        $this->charset = DB_CHARSET;

                if ( defined('DB_COLLATE') )
                        $this->collate = DB_COLLATE;

                $this->db_user = $dbuser;
                $this->db_password = $dbpassword;
                $this->db_name = $dbname;
                $this->db_host = $dbhost;

                $this->connect_to_db();
        }

        function __destruct() {
                return true;
        }

        function connect_to_db() {
                $this->dbh = @mysql_connect($this->db_host, $this->db_user, $this->db_password, true);
                if ( !$this->dbh ) {
                        $this->bail("
<h1>Error establishing a database connection</h1>
<p>This either means that the username and password information in your <code>wp-config.php</code> file is incorrect or we can't contact the database server at <code>$dbhost</code>. This could mean your host's database server is down.</p>
<ul>
        <li>Are you sure you have the correct username and password?</li>
        <li>Are you sure that you have typed the correct hostname?</li>
        <li>Are you sure that the database server is running?</li>
</ul>
<p>If you're unsure what these terms mean you should probably contact your host. If you still need help you can always visit the <a href='http://wordpress.org/support/'>WordPress Support Forums</a>.</p>
");
                        return;
                }

                $this->ready = true;

                if ( !empty($this->charset) && version_compare(mysql_get_server_info($this->dbh), '4.1.0', '>=') )
                        $this->query("SET NAMES '$this->charset'");

                $this->select($this->db_name);
        }

        function check_connection() {
                $maxcount = 2;
                $count = 0;

                $ping = mysql_ping( $this->dbh ) ;

                while ( !$ping && $count < $maxcount ) {
                        @mysql_close($this->dbh);
                        $this->connect_to_db();

                        $ping = mysql_ping( $this->dbh ) ;

                        if ( $ping )
                                break;

                        sleep(2);
                        $count++;
                }

                if ( !$ping )
                        $this->bail('Lost connection to server');
        }
 
        function set_prefix($prefix) {

                if ( preg_match('|[^a-z0-9_]|i', $prefix) )
                        return new WP_Error('invalid_db_prefix', 'Invalid database prefix'); // No gettext here

                $old_prefix = $this->prefix;
                $this->prefix = $prefix;

                foreach ( $this->tables as $table )
                        $this->$table = $this->prefix . $table;

                if ( defined('CUSTOM_USER_TABLE') )
                        $this->users = CUSTOM_USER_TABLE;

                if ( defined('CUSTOM_USER_META_TABLE') )
                        $this->usermeta = CUSTOM_USER_META_TABLE;

                return $old_prefix;
        }

        /**
         * Selects a database using the current class's $this->dbh
         * @param string $db name
         */
        function select($db) {
                if (!@mysql_select_db($db, $this->dbh)) {
                        $this->ready = false;
                        $this->bail("
<h1>Can&#8217;t select database</h1>
<p>We were able to connect to the database server (which means your username and password is okay) but not able to select the <code>$db</code> database.</p>
<ul>
<li>Are you sure it exists?</li>
<li>Does the user <code>".DB_USER."</code> have permission to use the <code>$db</code> database?</li>
<li>On some systems the name of your database is prefixed with your username, so it would be like username_wordpress. Could that be the problem?</li>
</ul>
<p>If you don't know how to setup a database you should <strong>contact your host</strong>. If all else fails you may find help at the <a href='http://wordpress.org/support/'>WordPress Support Forums</a>.</p>");
                        return;
                }
        }

        /**
         * Escapes content for insertion into the database, for security
         *
         * @param string $string
         * @return string query safe string
         */
        function escape($string) {
                return addslashes( $string );
                // Disable rest for now, causing problems
                /*
                if( !$this->dbh || version_compare( phpversion(), '4.3.0' ) == '-1' )
                        return mysql_escape_string( $string );
                else
                        return mysql_real_escape_string( $string, $this->dbh );
                */
        }

        /**
         * Escapes content by reference for insertion into the database, for security
         * @param string $s
         */
        function escape_by_ref(&$s) {
                $s = $this->escape($s);
        }

        /**
         * Prepares a SQL query for safe use, using sprintf() syntax
         */
        function prepare($args=NULL) {
                if ( NULL === $args )
                        return;
                $args = func_get_args();
                $query = array_shift($args);
                $query = str_replace("'%s'", '%s', $query); // in case someone mistakenly already singlequoted it
                $query = str_replace('"%s"', '%s', $query); // doublequote unquoting
                $query = str_replace('%s', "'%s'", $query); // quote the strings
                array_walk($args, array(&$this, 'escape_by_ref'));
                return @vsprintf($query, $args);
        }

        // ==================================================================
        //      Print SQL/DB error.

        function print_error($str = '') {
                global $EZSQL_ERROR;

                if (!$str) $str = mysql_error($this->dbh);
                $EZSQL_ERROR[] =
                array ('query' => $this->last_query, 'error_str' => $str);

                if ( $this->suppress_errors )
                        return false;

                $error_str = "WordPress database error $str for query $this->last_query";
                if ( $caller = $this->get_caller() )
                        $error_str .= " made by $caller";

                $log_error = true;
                if ( ! function_exists('error_log') )
                        $log_error = false;

                $log_file = @ini_get('error_log');
                if ( !empty($log_file) && ('syslog' != $log_file) && !is_writable($log_file) )
                        $log_error = false;

                if ( $log_error )
                        @error_log($error_str, 0);

                // Is error output turned on or not..
                if ( !$this->show_errors )
                        return false;

                $str = htmlspecialchars($str, ENT_QUOTES);
                $query = htmlspecialchars($this->last_query, ENT_QUOTES);

                // If there is an error then take note of it
                print "<div id='error'>
                <p class='wpdberror'><strong>WordPress database error:</strong> [$str]<br />
                <code>$query</code></p>
                </div>";
        }

        // ==================================================================
        //      Turn error handling on or off..

        function show_errors( $show = true ) {
                $errors = $this->show_errors;
                $this->show_errors = $show;
                return $errors;
        }

        function hide_errors() {
                $show = $this->show_errors;
                $this->show_errors = false;
                return $show;
        }

        function suppress_errors( $suppress = true ) {
                $errors = $this->suppress_errors;
                $this->suppress_errors = $suppress;
                return $errors;
        }

        // ==================================================================
        //      Kill cached query results

        function flush() {
                $this->last_result = array();
                $this->col_info = null;
                $this->last_query = null;
        }

        // ==================================================================
        //      Basic Query     - see docs for more detail

        function query($query) {
                if ( ! $this->ready )
                        return false;

                // filter the query, if filters are available
                // NOTE: some queries are made before the plugins have been loaded, and thus cannot be filtered with this method
                if ( function_exists('apply_filters') )
                        $query = apply_filters('query', $query);

                // initialise return
                $return_val = 0;
                $this->flush();

                // Log how the function was called
                $this->func_call = "\$db->query(\"$query\")";

                // Keep track of the last query for debug..
                $this->last_query = $query;

                // Perform the query via std mysql_query function..
                if (SAVEQUERIES)
                        $this->timer_start();

                $this->result = @mysql_query($query, $this->dbh);
                ++$this->num_queries;

                if (SAVEQUERIES)
                        $this->queries[] = array( $query, $this->timer_stop(), $this->get_caller() );

                // If there is an error then take note of it..
                if ( $this->last_error = mysql_error($this->dbh) ) {
                        $errno = mysql_errno();
                        if ( 2006 == $errno || 2013 == $errno ) {
                                $this->check_connection();
                                $this->result = @mysql_query($query, $this->dbh);
                                if ( $this->last_error = mysql_error($this->dbh) ) {
                                        $this->print_error();
                                        return false;
                                }
                        } else {
                                $this->print_error();
                                return false;
                        }
                }

                if ( preg_match("/^\\s*(insert|delete|update|replace) /i",$query) ) {
                        $this->rows_affected = mysql_affected_rows($this->dbh);
                        // Take note of the insert_id
                        if ( preg_match("/^\\s*(insert|replace) /i",$query) ) {
                                $this->insert_id = mysql_insert_id($this->dbh);
                        }
                        // Return number of rows affected
                        $return_val = $this->rows_affected;
                } else {
                        $i = 0;
                        while ($i < @mysql_num_fields($this->result)) {
                                $this->col_info[$i] = @mysql_fetch_field($this->result);
                                $i++;
                        }
                        $num_rows = 0;
                        while ( $row = @mysql_fetch_object($this->result) ) {
                                $this->last_result[$num_rows] = $row;
                                $num_rows++;
                        }

                        @mysql_free_result($this->result);

                        // Log number of rows the query returned
                        $this->num_rows = $num_rows;

                        // Return number of rows selected
                        $return_val = $this->num_rows;
                }

                return $return_val;
        }

        /**
         * Insert an array of data into a table
         * @param string $table WARNING: not sanitized!
         * @param array $data should not already be SQL-escaped
         * @return mixed results of $this->query()
         */
        function insert($table, $data) {
                $data = add_magic_quotes($data);
                $fields = array_keys($data);
                return $this->query("INSERT INTO $table (`" . implode('`,`',$fields) . "`) VALUES ('".implode("','",$data)."')");
        }

        /**
         * Update a row in the table with an array of data
         * @param string $table WARNING: not sanitized!
         * @param array $data should not already be SQL-escaped
         * @param array $where a named array of WHERE column => value relationships.  Multiple member pairs will be joined with ANDs.  WARNING: the column names are not currently sanitized!
         * @return mixed results of $this->query()
         */
        function update($table, $data, $where){
                $data = add_magic_quotes($data);
                $bits = $wheres = array();
                foreach ( array_keys($data) as $k )
                        $bits[] = "`$k` = '$data[$k]'";

                if ( is_array( $where ) )
                        foreach ( $where as $c => $v )
                                $wheres[] = "$c = '" . $this->escape( $v ) . "'";
                else
                        return false;
                return $this->query( "UPDATE $table SET " . implode( ', ', $bits ) . ' WHERE ' . implode( ' AND ', $wheres ) . ' LIMIT 1' );
        }

        /**
         * Get one variable from the database
         * @param string $query (can be null as well, for caching, see codex)
         * @param int $x = 0 row num to return
         * @param int $y = 0 col num to return
         * @return mixed results
         */
        function get_var($query=null, $x = 0, $y = 0) {
                $this->func_call = "\$db->get_var(\"$query\",$x,$y)";
                if ( $query )
                        $this->query($query);

                // Extract var out of cached results based x,y vals
                if ( !empty( $this->last_result[$y] ) ) {
                        $values = array_values(get_object_vars($this->last_result[$y]));
                }

                // If there is a value return it else return null
                return (isset($values[$x]) && $values[$x]!=='') ? $values[$x] : null;
        }

        /**
         * Get one row from the database
         * @param string $query
         * @param string $output ARRAY_A | ARRAY_N | OBJECT
         * @param int $y row num to return
         * @return mixed results
         */
        function get_row($query = null, $output = OBJECT, $y = 0) {
                $this->func_call = "\$db->get_row(\"$query\",$output,$y)";
                if ( $query )
                        $this->query($query);
                else
                        return null;

                if ( !isset($this->last_result[$y]) )
                        return null;

                if ( $output == OBJECT ) {
                        return $this->last_result[$y] ? $this->last_result[$y] : null;
                } elseif ( $output == ARRAY_A ) {
                        return $this->last_result[$y] ? get_object_vars($this->last_result[$y]) : null;
                } elseif ( $output == ARRAY_N ) {
                        return $this->last_result[$y] ? array_values(get_object_vars($this->last_result[$y])) : null;
                } else {
                        $this->print_error(" \$db->get_row(string query, output type, int offset) -- Output type must be one of: OBJECT, ARRAY_A, ARRAY_N");
                }
        }

        /**
         * Gets one column from the database
         * @param string $query (can be null as well, for caching, see codex)
         * @param int $x col num to return
         * @return array results
         */
        function get_col($query = null , $x = 0) {
                if ( $query )
                        $this->query($query);

                $new_array = array();
                // Extract the column values
                for ( $i=0; $i < count($this->last_result); $i++ ) {
                        $new_array[$i] = $this->get_var(null, $x, $i);
                }
                return $new_array;
        }

        /**
         * Return an entire result set from the database
         * @param string $query (can also be null to pull from the cache)
         * @param string $output ARRAY_A | ARRAY_N | OBJECT_K | OBJECT
         * @return mixed results
         */
        function get_results($query = null, $output = OBJECT) {
                $this->func_call = "\$db->get_results(\"$query\", $output)";

                if ( $query )
                        $this->query($query);
                else
                        return null;

                if ( $output == OBJECT ) {
                        // Return an integer-keyed array of row objects
                        return $this->last_result;
                } elseif ( $output == OBJECT_K ) {
                        // Return an array of row objects with keys from column 1
                        // (Duplicates are discarded)
                        foreach ( $this->last_result as $row ) {
                                $key = array_shift( get_object_vars( $row ) );
                                if ( !isset( $new_array[ $key ] ) )
                                        $new_array[ $key ] = $row;
                        }
                        return $new_array;
                } elseif ( $output == ARRAY_A || $output == ARRAY_N ) {
                        // Return an integer-keyed array of...
                        if ( $this->last_result ) {
                                $i = 0;
                                foreach( $this->last_result as $row ) {
                                        if ( $output == ARRAY_N ) {
                                                // ...integer-keyed row arrays
                                                $new_array[$i] = array_values( get_object_vars( $row ) );
                                        } else {
                                                // ...column name-keyed row arrays
                                                $new_array[$i] = get_object_vars( $row );
                                        }
                                        ++$i;
                                }
                                return $new_array;
                        }
                }
        }

        /**
         * Grabs column metadata from the last query
         * @param string $info_type one of name, table, def, max_length, not_null, primary_key, multiple_key, unique_key, numeric, blob, type, unsigned, zerofill
         * @param int $col_offset 0: col name. 1: which table the col's in. 2: col's max length. 3: if the col is numeric. 4: col's type
         * @return mixed results
         */
        function get_col_info($info_type = 'name', $col_offset = -1) {
                if ( $this->col_info ) {
                        if ( $col_offset == -1 ) {
                                $i = 0;
                                foreach($this->col_info as $col ) {
                                        $new_array[$i] = $col->{$info_type};
                                        $i++;
                                }
                                return $new_array;
                        } else {
                                return $this->col_info[$col_offset]->{$info_type};
                        }
                }
        }

        /**
         * Starts the timer, for debugging purposes
         */
        function timer_start() {
                $mtime = microtime();
                $mtime = explode(' ', $mtime);
                $this->time_start = $mtime[1] + $mtime[0];
                return true;
        }

        /**
         * Stops the debugging timer
         * @return int total time spent on the query, in milliseconds
         */
        function timer_stop() {
                $mtime = microtime();
                $mtime = explode(' ', $mtime);
                $time_end = $mtime[1] + $mtime[0];
                $time_total = $time_end - $this->time_start;
                return $time_total;
        }

        /**
         * Wraps fatal errors in a nice header and footer and dies.
         * @param string $message
         */
        function bail($message) { // Just wraps errors in a nice header and footer
                if ( !$this->show_errors ) {
                        if ( class_exists('WP_Error') )
                                $this->error = new WP_Error('500', $message);
                        else
                                $this->error = $message;
                        return false;
                }
                wp_die($message);
        }

        /**
         * Checks wether of not the database version is high enough to support the features WordPress uses
         * @global $wp_version
         */
        function check_database_version()
        {
                global $wp_version;
                // Make sure the server has MySQL 4.0
                $mysql_version = preg_replace('|[^0-9\.]|', '', @mysql_get_server_info($this->dbh));
                if ( version_compare($mysql_version, '4.0.0', '<') )
                        return new WP_Error('database_version',sprintf(__('<strong>ERROR</strong>: WordPress %s requires MySQL 4.0.0 or higher'), $wp_version));
        }

        /**
         * This function is called when WordPress is generating the table schema to determine wether or not the current database
         * supports or needs the collation statements.
         */
        function supports_collation()
        {
                return ( version_compare(mysql_get_server_info($this->dbh), '4.1.0', '>=') );
        }

        /**
         * Get the name of the function that called wpdb.
         * @return string the name of the calling function
         */
        function get_caller() {
                // requires PHP 4.3+
                if ( !is_callable('debug_backtrace') )
                        return '';

                $bt = debug_backtrace();
                $caller = '';

                foreach ( $bt as $trace ) {
                        if ( @$trace['class'] == __CLASS__ )
                                continue;
                        elseif ( strtolower(@$trace['function']) == 'call_user_func_array' )
                                continue;
                        elseif ( strtolower(@$trace['function']) == 'apply_filters' )
                                continue;
                        elseif ( strtolower(@$trace['function']) == 'do_action' )
                                continue;

                        $caller = $trace['function'];
                        break;
                }
                return $caller;
        }

}

if ( ! isset($wpdb) )
        $wpdb = new wpdb(DB_USER, DB_PASSWORD, DB_NAME, DB_HOST);
?>