cvm/frontend/module.login.php

<?php
/*
 * CVM is more free software. It is licensed under the WTFPL, which
 * allows you to do pretty much anything with it, without having to
 * ask permission. Commercial use is allowed, and no attribution is
 * required. We do politely request that you share your modifications
 * to benefit other developers, but you are under no enforced
 * obligation to do so :)
 * 
 * Please read the accompanying LICENSE document for the full WTFPL
 * licensing text.
 */

if(!isset($_CVM)) { die("Unauthorized."); }

if($sLoggedIn === true)
{
	// TODO: alert the user that he will switch to a different account, or disable if it is not allowed to have multiple accounts
}

$sError = "";
$sFieldUsername = "";
$render_form = true;

if(isset($_POST['submit']))
{
	$sUsername = mysql_real_escape_string($_POST['username']);
	$sFieldUsername = htmlentities($_POST['username']);
	
	if($result = mysql_query_cached("SELECT * FROM users WHERE `Username` = '{$sUsername}'"))
	{
		$sLoginUser = new User($result);
		
		if($sLoginUser->VerifyPassword($_POST['password']))
		{
			$_SESSION['userid'] = $sLoginUser->sId;
			header("Location: /");
			die();
		}
		else
		{
			$err = new CPHPErrorHandler(CPHP_ERRORHANDLER_TYPE_ERROR, $locale->strings['error-login-invalid-title'], $locale->strings['error-login-invalid-text']);
			$sError .= $err->Render();
		}
	}
	else
	{
		$err = new CPHPErrorHandler(CPHP_ERRORHANDLER_TYPE_ERROR, $locale->strings['error-login-invalid-title'], $locale->strings['error-login-invalid-text']);
		$sError .= $err->Render();
	}
}

$sMainContents = Templater::AdvancedParse("login", $locale->strings, array(
	'error'			=> $sError,
	'field-username'	=> $sFieldUsername
));