albertlast / SMF2.1

/**

 * The purpose of this file is... errors. (hard to guess, I guess?)  It takes

 * care of logging, error messages, error handling, database errors, and

 * error log administration.

 *

 * Simple Machines Forum (SMF)

 *

 * @package SMF

 * @author Simple Machines https://www.simplemachines.org

 * @copyright 2025 Simple Machines and individual contributors

 * @license https://www.simplemachines.org/about/smf/license.php BSD

 *

 * @version 2.1.5

 */

if (!defined('SMF'))

	die('No direct access...');

/**

 * Log an error, if the error logging is enabled.

 * filename and line should be __FILE__ and __LINE__, respectively.

 * Example use:

 *  die(log_error($msg));

 *

 * @param string $error_message The message to log

 * @param string|bool $error_type The type of error

 * @param string $file The name of the file where this error occurred

 * @param int $line The line where the error occurred

 * @return string The message that was logged

 */

function log_error($error_message, $error_type = 'general', $file = null, $line = null)

{

	global $modSettings, $sc, $user_info, $smcFunc, $scripturl, $last_error, $context, $db_show_debug;

	static $tried_hook = false;

	static $error_call = 0;

	$error_call++;

	// Collect a backtrace

	if (!isset($db_show_debug) || $db_show_debug === false)

		$backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);

	else

		$backtrace = debug_backtrace();

	if (empty($modSettings['enableErrorLogging']))

		return $error_message;

	// Basically, htmlspecialchars it minus &. (for entities!)

	$error_message = strtr($error_message, array('<' => '&lt;', '>' => '&gt;', '"' => '&quot;'));

	$error_message = strtr($error_message, array('&lt;br /&gt;' => '<br>', '&lt;br&gt;' => '<br>', '&lt;b&gt;' => '<strong>', '&lt;/b&gt;' => '</strong>', "\n" => '<br>'));

	// Just in case there's no id_member or IP set yet.

	if (empty($user_info['id']))

		$user_info['id'] = 0;

	if (empty($user_info['ip']))

		$user_info['ip'] = '';

	// Find the best query string we can...

	$query_string = empty($_SERVER['QUERY_STRING']) ? (empty($_SERVER['REQUEST_URL']) ? '' : str_replace($scripturl, '', $_SERVER['REQUEST_URL'])) : $_SERVER['QUERY_STRING'];

		$query_string .= ($query_string == '' ? 'board=' : ';board=') . $_POST['board'];

	// What types of categories do we have?

	$known_error_types = array(

		'general',

		'critical',

		'database',

		'undefined_vars',

		'user',

		'ban',

		'template',

		'debug',

		'cron',

		'paidsubs',

		'backup',

		'login',

	);

	// This prevents us from infinite looping if the hook or call produces an error.

	$other_error_types = array();

	if (empty($tried_hook))

	{

		$tried_hook = true;

		// Allow the hook to change the error_type and know about the error.

		call_integration_hook('integrate_error_types', array(&$other_error_types, &$error_type, $error_message, $file, $line));

		$known_error_types = array_merge($known_error_types, $other_error_types);

	}

	// Make sure the category that was specified is a valid one

	$error_type = in_array($error_type, $known_error_types) && $error_type !== true ? $error_type : 'general';

	// leave out the call to log_error

	array_splice($backtrace, 0, 1);

	$backtrace = !empty($smcFunc['json_encode']) ? $smcFunc['json_encode']($backtrace) : json_encode($backtrace);

	// Don't log the same error countless times, as we can get in a cycle of depression...

	$error_info = array($user_info['id'], time(), $user_info['ip'], $query_string, $error_message, (string) $sc, $error_type, $file, $line, $backtrace);

	if (empty($last_error) || $last_error != $error_info)

	{

		// Insert the error into the database.

		$smcFunc['db_error_insert']($error_info);

		$last_error = $error_info;

		// Get an error count, if necessary

		if (!isset($context['num_errors']))

		{

			$query = $smcFunc['db_query']('', '

				SELECT COUNT(*)

				FROM {db_prefix}log_errors',

				array()

			);

			list($context['num_errors']) = $smcFunc['db_fetch_row']($query);

			$smcFunc['db_free_result']($query);

		}

		else

			$context['num_errors']++;

	}

	// reset error call

	$error_call = 0;

	// Return the message to make things simpler.

	return $error_message;

}

/**

 * An irrecoverable error. This function stops execution and displays an error message.

 * It logs the error message if $log is specified.

 *

 * @param string $error The error message

 * @param string|bool $log = 'general' What type of error to log this as (false to not log it))

 * @param int $status The HTTP status code associated with this error

 */

function fatal_error($error, $log = 'general', $status = 500)

{

	global $txt;

	// Send the appropriate HTTP status header - set this to 0 or false if you don't want to send one at all

	if (!empty($status))

		send_http_status($status);

}

/**

 * Shows a fatal error with a message stored in the language file.

 *

 * This function stops execution and displays an error message by key.

 *  - uses the string with the error_message_key key.

 *  - logs the error in the forum's default language while displaying the error

 *    message in the user's language.

 *  - uses Errors language file and applies the $sprintf information if specified.

 *  - the information is logged if log is specified.

 *

 * @param string $error The error message

 * @param string|false $log The type of error, or false to not log it

 * @param array $sprintf An array of data to be sprintf()'d into the specified message

 * @param int $status = false The HTTP status code associated with this error

 */

function fatal_lang_error($error, $log = 'general', $sprintf = array(), $status = 403)

{

	global $txt, $language, $user_info, $context;

	static $fatal_error_called = false;

	// Ensure this is an array.

	$sprintf = (array) $sprintf;

	// Send the status header - set this to 0 or false if you don't want to send one at all

	if (!empty($status))

		send_http_status($status);

	// Try to load a theme if we don't have one.

	if (empty($context['theme_loaded']) && empty($fatal_error_called))

	{

		$fatal_error_called = true;

		loadTheme();

	}

	// Attempt to load the text string.

	loadLanguage('Errors');

	if (empty($txt[$error]))

		$error_message = $error;

	else

	if ($log)

	{

		loadLanguage('Errors', $language);

		$reload_lang_file = $language != $user_info['language'];

		if (empty($txt[$error]))

			$error_message = $error;

		else

			$error_message = empty($sprintf) ? $txt[$error] : vsprintf($txt[$error], $sprintf);

		log_error($error_message, $log);

	}

	// Load the language file, only if it needs to be reloaded

	if ($reload_lang_file && !empty($txt[$error]))

	{

		loadLanguage('Errors');

		$error_message = empty($sprintf) ? $txt[$error] : vsprintf($txt[$error], $sprintf);

	}

	log_error_online($error, $sprintf);

	setup_fatal_error_context($error_message, $error);

}

/**

 * Handler for standard error messages, standard PHP error handler replacement.

 * It dies with fatal_error() if the error_level matches with error_reporting.

 *

 * @param int $error_level A pre-defined error-handling constant (see {@link https://php.net/errorfunc.constants})

 * @param string $error_string The error message

 * @param string $file The file where the error occurred

 * @param int $line The line where the error occurred

 */

function smf_error_handler($error_level, $error_string, $file, $line)

{

	global $settings, $modSettings, $db_show_debug;

	// Error was suppressed with the @-operator.

	if (error_reporting() == 0 || error_reporting() == (E_ERROR | E_PARSE | E_CORE_ERROR | E_COMPILE_ERROR | E_USER_ERROR | E_RECOVERABLE_ERROR))

		return true;

	// Ignore errors that should should not be logged.

	$error_match = error_reporting() & $error_level;

	if (empty($error_match) || empty($modSettings['enableErrorLogging']))

		return false;

	if (strpos($file, 'eval()') !== false && !empty($settings['current_include_filename']))

	{

		$array = debug_backtrace();

		$count = count($array);

		for ($i = 0; $i < $count; $i++)

		{

			if ($array[$i]['function'] != 'loadSubTemplate')

				continue;

			// This is a bug in PHP, with eval, it seems!

			if (empty($array[$i]['args']))

				$i++;

			break;

		}

		if (isset($array[$i]) && !empty($array[$i]['args']))

			$file = realpath($settings['current_include_filename']) . ' (' . $array[$i]['args'][0] . ' sub template - eval?)';

		else

			$file = realpath($settings['current_include_filename']) . ' (eval?)';

	}

	if (isset($db_show_debug) && $db_show_debug === true)

	{

		// Commonly, undefined indexes will occur inside attributes; try to show them anyway!

		if ($error_level % 255 != E_ERROR)

		{

			$temporary = ob_get_contents();

			if (substr($temporary, -2) == '="')

				echo '"';

		}

		// Debugging!  This should look like a PHP error message.

		echo '<br>

<strong>', $error_level % 255 == E_ERROR ? 'Error' : ($error_level % 255 == E_WARNING ? 'Warning' : 'Notice'), '</strong>: ', $error_string, ' in <strong>', $file, '</strong> on line <strong>', $line, '</strong><br>';

	}

	$error_type = stripos($error_string, 'undefined') !== false ? 'undefined_vars' : 'general';

	$message = log_error($error_level . ': ' . $error_string, $error_type, $file, $line);

	// Let's give integrations a chance to ouput a bit differently

	call_integration_hook('integrate_output_error', array($message, $error_type, $error_level, $file, $line));

	// Dying on these errors only causes MORE problems (blank pages!)

	if ($file == 'Unknown')

		return;

	// If this is an E_ERROR or E_USER_ERROR.... die.  Violently so.

	if ($error_level % 255 == E_ERROR)

		obExit(false);

	else

		return;

	// If this is an E_ERROR, E_USER_ERROR, E_WARNING, or E_USER_WARNING.... die.  Violently so.

	if ($error_level % 255 == E_ERROR || $error_level % 255 == E_WARNING)

		fatal_error(allowedTo('admin_forum') ? $message : $error_string, false);

 * Generic handler for uncaught exceptions.

 *

 * Always ends execution.

 *

 * @param \Throwable $e The uncaught exception.

 */

function smf_exception_handler(\Throwable $e)

{

	global $modSettings, $txt;

	loadLanguage('Errors');

	$message = $txt[$e->getMessage()] ?? $e->getMessage();

	if (!empty($modSettings['enableErrorLogging'])) {

		log_error($message, 'general', $e->getFile(), $e->getLine());

	}

	fatal_error($message, false);

}

/**

 * It is called by {@link fatal_error()} and {@link fatal_lang_error()}.

 *

 * @uses template_fatal_error()

 *

 * @param string $error_message The error message

 * @param string $error_code An error code

 * @return void|false Normally doesn't return anything, but returns false if a recursive loop is detected

 */

function setup_fatal_error_context($error_message, $error_code = null)

{

	global $context, $txt, $ssi_on_error_method;

	static $level = 0;

	// Attempt to prevent a recursive loop.

	++$level;

	if ($level > 1)

	$context['robot_no_index'] = true;

	if (!isset($context['error_title']))

		$context['error_title'] = $txt['error_occured'];

	$context['error_message'] = isset($context['error_message']) ? $context['error_message'] : $error_message;

	$context['error_code'] = isset($error_code) ? 'id="' . $error_code . '" ' : '';

	$context['error_link'] = isset($context['error_link']) ? $context['error_link'] : 'javascript:document.location=document.referrer';

	if (empty($context['page_title']))

		$context['page_title'] = $context['error_title'];

	loadTemplate('Errors');

	$context['sub_template'] = 'fatal_error';

	// If this is SSI, what do they want us to do?

	if (SMF == 'SSI')

	{

		if (!empty($ssi_on_error_method) && $ssi_on_error_method !== true && is_callable($ssi_on_error_method))

			$ssi_on_error_method();

		elseif (empty($ssi_on_error_method) || $ssi_on_error_method !== true)

			loadSubTemplate('fatal_error');

	{

		// We can't rely on even having language files available.

		if (defined('FROM_CLI') && FROM_CLI)

	obExit(null, true, false, true);

	/* DO NOT IGNORE:

		If you are creating a bridge to SMF or modifying this function, you MUST

		make ABSOLUTELY SURE that this function quits and DOES NOT RETURN TO NORMAL

 * Show a message for the (full block) maintenance mode.

 * It shows a complete page independent of language files or themes.

 * It is used only if $maintenance = 2 in Settings.php.

 * It stops further execution of the script.

 */

function display_maintenance_message()

{

	global $maintenance, $mtitle, $mmessage;

	set_fatal_error_headers();

	if (!empty($maintenance))

		echo '<!DOCTYPE html>

<html>

	<head>

		<meta name="robots" content="noindex">

		<title>', $mtitle, '</title>

	</head>

	<body>

		<h3>', $mtitle, '</h3>

		', $mmessage, '

 * Show an error message for the connection problems.

 * It shows a complete page independent of language files or themes.

 * It is used only if there's no way to connect to the database.

 * It stops further execution of the script.

 */

function display_db_error()

{

	global $mbname, $modSettings, $maintenance;

	global $db_connection, $webmaster_email, $db_last_error, $db_error_send, $smcFunc, $sourcedir, $cache_enable;

	require_once($sourcedir . '/Logging.php');

	set_fatal_error_headers();

	// For our purposes, we're gonna want this on if at all possible.

	$cache_enable = '1';

	if (($temp = cache_get_data('db_last_error', 600)) !== null)

		$db_last_error = max($db_last_error, $temp);

	if ($db_last_error < time() - 3600 * 24 * 3 && empty($maintenance) && !empty($db_error_send))

		$db_error = @$smcFunc['db_error']($db_connection);

		@mail($webmaster_email, $mbname . ': SMF Database Error!', 'There has been a problem with the database!' . ($db_error == '' ? '' : "\n" . $smcFunc['db_title'] . ' reported:' . "\n" . $db_error) . "\n\n" . 'This is a notice email to let you know that SMF could not connect to the database, contact your host if this continues.');

	}

	// What to do?  Language files haven't and can't be loaded yet...

	echo '<!DOCTYPE html>

<html>

	<head>

		<meta name="robots" content="noindex">

		<title>Connection Problems</title>

	</head>

	<body>

		<h3>Connection Problems</h3>

		Sorry, SMF was unable to connect to the database.  This may be caused by the server being busy.  Please try again later.

 * Show an error message for load average blocking problems.

 * It shows a complete page independent of language files or themes.

 * It is used only if the load averages are too high to continue execution.

 * It stops further execution of the script.

 */

function display_loadavg_error()

{

	// If this is a load average problem, display an appropriate message (but we still don't have language files!)

	set_fatal_error_headers();

	echo '<!DOCTYPE html>

<html>

	<head>

		<meta name="robots" content="noindex">

		<title>Temporarily Unavailable</title>

	</head>

	<body>

		<h3>Temporarily Unavailable</h3>

		Due to high stress on the server the forum is temporarily unavailable.  Please try again later.

 * Small utility function for fatal error pages.

 * Used by {@link display_db_error()}, {@link display_loadavg_error()},

 * {@link display_maintenance_message()}

 */

function set_fatal_error_headers()

{

	if (headers_sent())

		return;

	// Don't cache this page!

	header('expires: Mon, 26 Jul 1997 05:00:00 GMT');

	header('last-modified: ' . gmdate('D, d M Y H:i:s') . ' GMT');

	header('cache-control: no-cache');

	// Send the right error codes.

	send_http_status(503, 'Service Temporarily Unavailable');

	header('status: 503 Service Temporarily Unavailable');

	header('retry-after: 3600');

}

/**

 * Small utility function for fatal error pages.

 * Used by fatal_error(), fatal_lang_error()

 *

 * @param string $error The error

 * @param array $sprintf An array of data to be sprintf()'d into the specified message

 */

function log_error_online($error, $sprintf = array())

{

	global $smcFunc, $user_info, $modSettings;

	// Don't bother if Who's Online is disabled.

	if (empty($modSettings['who_enabled']))

	// First, we have to get the online log, because we need to break apart the serialized string.

	$request = $smcFunc['db_query']('', '

		SELECT url

		FROM {db_prefix}log_online

		WHERE session = {string:session}',

		array(

			'session' => $session_id,

		)

	);

	if ($smcFunc['db_num_rows']($request) != 0)

	{

		// If this happened very early on in SMF startup, $smcFunc may not fully be defined.

		if (!isset($smcFunc['json_decode']))

		{

			$smcFunc['json_decode'] = 'smf_json_decode';

			$smcFunc['json_encode'] = 'json_encode';

		}

		list ($url) = $smcFunc['db_fetch_row']($request);

		$url = $smcFunc['json_decode']($url, true);

		$url['error'] = $error;

		// Url field got a max length of 1024 in db

		if (strlen($url['error']) > 500)

			$url['error'] = substr($url['error'], 0, 500);

		if (!empty($sprintf))

			$url['error_params'] = $sprintf;

		$smcFunc['db_query']('', '

			UPDATE {db_prefix}log_online

			SET url = {string:url}

			WHERE session = {string:session}',

			array(

				'url' => $smcFunc['json_encode']($url),

				'session' => $session_id,

			)

		);

	}

	$smcFunc['db_free_result']($request);

}