WordPress/wp-admin/setup-config.php

<?php
/**
 * Retrieves and creates the wp-config.php file.
 *
 * The permissions for the base directory must allow for writing files in order
 * for the wp-config.php to be created using this page.
 *
 * @internal This file must be parsable by PHP4.
 *
 * @package WordPress
 * @subpackage Administration
 */

/**
 * We are installing.
 *
 * @package WordPress
 */
define('WP_INSTALLING', true);

/**
 * We are blissfully unaware of anything.
 */
define('WP_SETUP_CONFIG', true);

/**
 * Disable error reporting
 *
 * Set this to error_reporting( E_ALL ) or error_reporting( E_ALL | E_STRICT ) for debugging
 */
error_reporting(0);

/**#@+
 * These three defines are required to allow us to use require_wp_db() to load
 * the database class while being wp-content/db.php aware.
 * @ignore
 */
define('ABSPATH', dirname(dirname(__FILE__)).'/');
define('WPINC', 'wp-includes');
define('WP_CONTENT_DIR', ABSPATH . 'wp-content');
define('WP_DEBUG', false);
/**#@-*/

require(ABSPATH . WPINC . '/load.php');
require(ABSPATH . WPINC . '/version.php');

// Also loads functions.php, plugin.php, l10n.php, pomo/mo.php (all required by setup-config.php)
wp_load_translations_early();

wp_check_php_mysql_versions();

require_once(ABSPATH . WPINC . '/compat.php');
require_once(ABSPATH . WPINC . '/class-wp-error.php');

if ( ! file_exists( ABSPATH . 'wp-config-sample.php' ) )
	wp_die( __( 'Sorry, I need a wp-config-sample.php file to work from. Please re-upload this file from your WordPress installation.' ) );

$config_file = file(ABSPATH . 'wp-config-sample.php');

// Check if wp-config.php has been created
if ( file_exists( ABSPATH . 'wp-config.php' ) )
	wp_die( '<p>' . sprintf( __( "The file 'wp-config.php' already exists. If you need to reset any of the configuration items in this file, please delete it first. You may try <a href='%s'>installing now</a>." ), 'install.php' ) . '</p>' );

// Check if wp-config.php exists above the root directory but is not part of another install
if ( file_exists(ABSPATH . '../wp-config.php' ) && ! file_exists( ABSPATH . '../wp-settings.php' ) )
	wp_die( '<p>' . sprintf( __( "The file 'wp-config.php' already exists one level above your WordPress installation. If you need to reset any of the configuration items in this file, please delete it first. You may try <a href='install.php'>installing now</a>."), 'install.php' ) . '</p>' );

$step = isset( $_GET['step'] ) ? (int) $_GET['step'] : 0;

/**
 * Display setup wp-config.php file header.
 *
 * @ignore
 * @since 2.3.0
 * @package WordPress
 * @subpackage Installer_WP_Config
 */
function display_header() {
	global $wp_version;

	header( 'Content-Type: text/html; charset=utf-8' );
?>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"<?php if ( is_rtl() ) echo ' dir="rtl"'; ?>>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title><?php _e( 'WordPress &rsaquo; Setup Configuration File' ); ?></title>
<link rel="stylesheet" href="css/install.css?ver=<?php echo preg_replace( '/[^0-9a-z\.-]/i', '', $wp_version ); ?>" type="text/css" />

</head>
<body<?php if ( is_rtl() ) echo ' class="rtl"'; ?>>
<h1 id="logo"><img alt="WordPress" src="images/wordpress-logo.png?ver=20120216" /></h1>
<?php
}//end function display_header();

switch($step) {
	case 0:
		display_header();
?>

<p><?php _e( 'Welcome to WordPress. Before getting started, we need some information on the database. You will need to know the following items before proceeding.' ) ?></p>
<ol>
	<li><?php _e( 'Database name' ); ?></li>
	<li><?php _e( 'Database username' ); ?></li>
	<li><?php _e( 'Database password' ); ?></li>
	<li><?php _e( 'Database host' ); ?></li>
	<li><?php _e( 'Table prefix (if you want to run more than one WordPress in a single database)' ); ?></li>
</ol>
<p><strong><?php _e( "If for any reason this automatic file creation doesn't work, don't worry. All this does is fill in the database information to a configuration file. You may also simply open <code>wp-config-sample.php</code> in a text editor, fill in your information, and save it as <code>wp-config.php</code>. </strong></p>
<p>In all likelihood, these items were supplied to you by your Web Host. If you do not have this information, then you will need to contact them before you can continue. If you&#8217;re all ready&hellip;" ); ?></p>

<p class="step"><a href="setup-config.php?step=1<?php if ( isset( $_GET['noapi'] ) ) echo '&amp;noapi'; ?>" class="button"><?php _e( 'Let&#8217;s go!' ); ?></a></p>
<?php
	break;

	case 1:
		display_header();
	?>
<form method="post" action="setup-config.php?step=2">
	<p><?php _e( "Below you should enter your database connection details. If you're not sure about these, contact your host." ); ?></p>
	<table class="form-table">
		<tr>
			<th scope="row"><label for="dbname"><?php _e( 'Database Name' ); ?></label></th>
			<td><input name="dbname" id="dbname" type="text" size="25" value="wordpress" /></td>
			<td><?php _e( 'The name of the database you want to run WP in.' ); ?></td>
		</tr>
		<tr>
			<th scope="row"><label for="uname"><?php _e( 'User Name' ); ?></label></th>
			<td><input name="uname" id="uname" type="text" size="25" value="<?php echo htmlspecialchars( _x( 'username', 'example username' ), ENT_QUOTES ); ?>" /></td>
			<td><?php _e( 'Your MySQL username' ); ?></td>
		</tr>
		<tr>
			<th scope="row"><label for="pwd"><?php _e( 'Password' ); ?></label></th>
			<td><input name="pwd" id="pwd" type="text" size="25" value="<?php echo htmlspecialchars( _x( 'password', 'example password' ), ENT_QUOTES ); ?>" /></td>
			<td><?php _e( '&hellip;and your MySQL password.' ); ?></td>
		</tr>
		<tr>
			<th scope="row"><label for="dbhost"><?php _e( 'Database Host' ); ?></label></th>
			<td><input name="dbhost" id="dbhost" type="text" size="25" value="localhost" /></td>
			<td><?php _e( 'You should be able to get this info from your web host, if <code>localhost</code> does not work.' ); ?></td>
		</tr>
		<tr>
			<th scope="row"><label for="prefix"><?php _e( 'Table Prefix' ); ?></label></th>
			<td><input name="prefix" id="prefix" type="text" value="wp_" size="25" /></td>
			<td><?php _e( 'If you want to run multiple WordPress installations in a single database, change this.' ); ?></td>
		</tr>
	</table>
	<?php if ( isset( $_GET['noapi'] ) ) { ?><input name="noapi" type="hidden" value="1" /><?php } ?>
	<p class="step"><input name="submit" type="submit" value="<?php echo htmlspecialchars( __( 'Submit' ), ENT_QUOTES ); ?>" class="button" /></p>
</form>
<?php
	break;

	case 2:
	$dbname  = trim($_POST['dbname']);
	$uname   = trim($_POST['uname']);
	$passwrd = trim($_POST['pwd']);
	$dbhost  = trim($_POST['dbhost']);
	$prefix  = trim($_POST['prefix']);
	if ( empty($prefix) )
		$prefix = 'wp_';

	// Validate $prefix: it can only contain letters, numbers and underscores
	if ( preg_match( '|[^a-z0-9_]|i', $prefix ) )
		wp_die( __( '<strong>ERROR</strong>: "Table Prefix" can only contain numbers, letters, and underscores.' ) );

	// Test the db connection.
	/**#@+
	 * @ignore
	 */
	define('DB_NAME', $dbname);
	define('DB_USER', $uname);
	define('DB_PASSWORD', $passwrd);
	define('DB_HOST', $dbhost);
	/**#@-*/

	// We'll fail here if the values are no good.
	require_wp_db();
	if ( ! empty( $wpdb->error ) ) {
		$back = '<p class="step"><a href="setup-config.php?step=1" onclick="javascript:history.go(-1);return false;" class="button">' . __( 'Try Again' ) . '</a></p>';
		wp_die( $wpdb->error->get_error_message() . $back );
	}

	// Fetch or generate keys and salts.
	$no_api = isset( $_POST['noapi'] );
	if ( ! $no_api ) {
		require_once( ABSPATH . WPINC . '/class-http.php' );
		require_once( ABSPATH . WPINC . '/http.php' );
		wp_fix_server_vars();
		/**#@+
		 * @ignore
		 */
		function get_bloginfo() {
			return ( ( is_ssl() ? 'https://' : 'http://' ) . $_SERVER['HTTP_HOST'] . str_replace( $_SERVER['PHP_SELF'], '/wp-admin/setup-config.php', '' ) );
		}
		/**#@-*/
		$secret_keys = wp_remote_get( 'https://api.wordpress.org/secret-key/1.1/salt/' );
	}

	if ( $no_api || is_wp_error( $secret_keys ) ) {
		$secret_keys = array();
		require_once( ABSPATH . WPINC . '/pluggable.php' );
		for ( $i = 0; $i < 8; $i++ ) {
			$secret_keys[] = wp_generate_password( 64, true, true );
		}
	} else {
		$secret_keys = explode( "\n", wp_remote_retrieve_body( $secret_keys ) );
		foreach ( $secret_keys as $k => $v ) {
			$secret_keys[$k] = substr( $v, 28, 64 );
		}
	}

	$key = 0;
	foreach ( $config_file as &$line ) {
		if ( '$table_prefix  =' == substr( $line, 0, 16 ) ) {
			$line = '$table_prefix  = \'' . $prefix . "';\r\n";
			continue;
		}

		if ( ! preg_match( '/^define\(\'([A-Z_]+)\',([ ]+)/', $line, $match ) )
			continue;

		$constant = $match[1];
		$padding  = $match[2];

		switch ( $constant ) {
			case 'DB_NAME'     :
			case 'DB_USER'     :
			case 'DB_PASSWORD' :
			case 'DB_HOST'     :
				$line = "define('" . $constant . "'," . $padding . "'" . constant( $constant ) . "');\r\n";
				break;
			case 'AUTH_KEY'         :
			case 'SECURE_AUTH_KEY'  :
			case 'LOGGED_IN_KEY'    :
			case 'NONCE_KEY'        :
			case 'AUTH_SALT'        :
			case 'SECURE_AUTH_SALT' :
			case 'LOGGED_IN_SALT'   :
			case 'NONCE_SALT'       :
				$line = "define('" . $constant . "'," . $padding . "'" . $secret_keys[$key++] . "');\r\n";
				break;
		}
	}
	unset( $line );

	if ( ! is_writable(ABSPATH) ) :
		display_header();
?>
<p><?php _e( "Sorry, but I can't write the <code>wp-config.php</code> file." ); ?></p>
<p><?php _e( 'You can create the <code>wp-config.php</code> manually and paste the following text into it.' ); ?></p>
<textarea cols="98" rows="15" class="code"><?php
		foreach( $config_file as $line ) {
			echo htmlentities($line, ENT_COMPAT, 'UTF-8');
		}
?></textarea>
<p><?php _e( 'After you\'ve done that, click "Run the install."' ); ?></p>
<p class="step"><a href="install.php" class="button"><?php _e( 'Run the install' ); ?></a></p>
<?php
	else :
		$handle = fopen(ABSPATH . 'wp-config.php', 'w');
		foreach( $config_file as $line ) {
			fwrite($handle, $line);
		}
		fclose($handle);
		chmod(ABSPATH . 'wp-config.php', 0666);
		display_header();
?>
<p><?php _e( "All right sparky! You've made it through this part of the installation. WordPress can now communicate with your database. If you are ready, time now to&hellip;" ); ?></p>

<p class="step"><a href="install.php" class="button"><?php _e( 'Run the install' ); ?></a></p>
<?php
	endif;
	break;
}
?>
</body>
</html>