#304924: extends drupal_error_handler to manage exceptions. From: Damien Tournoud - Implement a _drupal_exception_handler, with a reimplementation of the "skip internal database functions" we had pre DB:TNG - Mark the handlers as private - Add supports for displaying functions and method names in the error message - General lifting of that key part of Drupal --- includes/common.inc | 127 ++++++++++++++++++++++++++++++---------- includes/database/database.inc | 7 -- 2 files changed, 96 insertions(+), 38 deletions(-) diff --git includes/common.inc includes/common.inc index 42cc5b7..ebe2601 100644 --- includes/common.inc +++ includes/common.inc @@ -583,50 +583,114 @@ function drupal_http_request($url, $headers = array(), $method = 'GET', $data = */ /** - * Log errors as defined by administrator. + * Custom PHP error handler: log errors as defined by administrator. * - * Error levels: - * - 0 = Log errors to database. - * - 1 = Log errors to database and to screen. + * @param $error_level + * The level of the error raised. + * @param $message + * The error message. + * @param $filename + * The filename that the error was raised in. + * @param $line + * The line number the error was raised at. + * @param $context + * An array that points to the active symbol table at the point the error occurred. */ -function drupal_error_handler($errno, $message, $filename, $line, $context) { +function _drupal_error_handler($error_level, $message, $filename, $line, $context) { // If the @ error suppression operator was used, error_reporting will have // been temporarily set to 0. if (error_reporting() == 0) { return; } + if ($error_level & (E_ALL)) { + // All these constants are documented at http://php.net/manual/en/errorfunc.constants.php + $types = array( + E_ERROR => 'Error', + E_WARNING => 'Warning', + E_PARSE => 'Parse error', + E_NOTICE => 'Notice', + E_CORE_ERROR => 'Core error', + E_CORE_WARNING => 'Core warning', + E_COMPILE_ERROR => 'Compile error', + E_COMPILE_WARNING => 'Compile warning', + E_USER_ERROR => 'User error', + E_USER_WARNING => 'User warning', + E_USER_NOTICE => 'User notice', + E_STRICT => 'Strict warning', + E_RECOVERABLE_ERROR => 'Recoverable fatal error' + ); + $backtrace = debug_backtrace(); + _drupal_log_error(isset($types[$errno]) ? $types[$error_level] : 'Unknown error', $message, $backtrace); + } +} - if ($errno & (E_ALL)) { - $types = array(1 => 'error', 2 => 'warning', 4 => 'parse error', 8 => 'notice', 16 => 'core error', 32 => 'core warning', 64 => 'compile error', 128 => 'compile warning', 256 => 'user error', 512 => 'user warning', 1024 => 'user notice', 2048 => 'strict warning', 4096 => 'recoverable fatal error'); - - // For database errors, we want the line number/file name of the place that - // the query was originally called, not _db_query(). - if (isset($context[DB_ERROR])) { - $backtrace = array_reverse(debug_backtrace()); - - // List of functions where SQL queries can originate. - $query_functions = array('db_query', 'pager_query', 'db_query_range', 'db_query_temporary', 'update_sql'); +/** + * Custom PHP exception handler: log uncaught exceptions and output a meaningful error message to the user. + * + * Uncaught exceptions are those not enclosed in a try/catch block. They are + * always fatal: the execution of the script will stop as soon as the exception + * handler exits. + * + * @param $exception + * The exception object that was thrown. + */ +function _drupal_exception_handler($exception) { + $backtrace = $exception->getTrace(); + // Add the line throwing the exception to the backtrace. + array_unshift($backtrace, array('line' => $exception->getLine(), 'file' => $exception->getFile())); - // Determine where query function was called, and adjust line/file - // accordingly. - foreach ($backtrace as $index => $function) { - if (in_array($function['function'], $query_functions)) { - $line = $backtrace[$index]['line']; - $filename = $backtrace[$index]['file']; - break; - } - } + // For PDOException errors, we try to return the initial caller, + // skipping internal functions of the database layer. + if ($exception instanceof PDOException) { + // The first element in the stack is the call, the second element gives us the caller. + // We skip calls that occured in one of the classes of the database layer + // or in one of its global functions. + $db_functions = array('db_query', 'pager_query', 'db_query_range', 'db_query_temporary', 'update_sql'); + while (($caller = $backtrace[1]) && + ((isset($caller['class']) && (strpos($caller['class'], 'Query') !== FALSE || strpos($caller['class'], 'Database') !== FALSE)) || + in_array($caller['function'], $db_functions))) { + // We remove that call. + array_shift($backtrace); } + } - $entry = $types[$errno] . ': ' . $message . ' in ' . $filename . ' on line ' . $line . '.'; + // Log the message to the watchdog and/or display it to the user. + _drupal_log_error('Uncaught exception', $exception->getMessage(), $backtrace); - // Force display of error messages in update.php. - if (variable_get('error_level', 1) == 1 || strstr($_SERVER['SCRIPT_NAME'], 'update.php')) { - drupal_set_message($entry, 'error'); - } + // Uncaught exceptions are always fatal in PHP. + // We try to display an error message to the user. + if (!isset($GLOBALS['theme'])) { + drupal_maintenance_theme(); + $type = 'maintenance_page'; + } + else { + $type = 'page'; + } + drupal_set_header('HTTP/1.1 503 Service unavailable'); + drupal_set_title(t('Error')); + print theme($type, t('The website encountered an unexpected error. Please try again later.')); + exit; +} - watchdog('php', '%message in %file on line %line.', array('%error' => $types[$errno], '%message' => $message, '%file' => $filename, '%line' => $line), WATCHDOG_ERROR); +/** + * Helper function to log a PHP error or exception to the watchdog and to optionally display it to the user. + * + * @param $type + * The type of the error (Error, Warning, ...). + * @param $message + * The message associated to the error. + * @param $backtrace + * The backtrace of function calls that led to this error. + */ +function _drupal_log_error($type, $message, $backtrace) { + $caller = _drupal_get_last_caller($backtrace); + + // Force display of error messages in update.php. + if (variable_get('error_level', 1) == 1 || strstr($_SERVER['SCRIPT_NAME'], 'update.php')) { + drupal_set_message(t('@type: %message in %function (line %line of %file).', array('@type' => $type, '%message' => $message, '%function' => $caller['function'], '%line' => $caller['line'], '%file' => $caller['file'])), 'error'); } + + watchdog('php', '%error: %message in %function (line %line of %file).', array('%error' => $type, '%message' => $message, '%function' => $caller['function'], '%file' => $caller['file'], '%line' => $caller['line']), WATCHDOG_ERROR); } /** @@ -2514,7 +2578,8 @@ function _drupal_bootstrap_full() { require_once DRUPAL_ROOT . '/includes/mail.inc'; require_once DRUPAL_ROOT . '/includes/actions.inc'; // Set the Drupal custom error handler. - set_error_handler('drupal_error_handler'); + set_error_handler('_drupal_error_handler'); + set_exception_handler('_drupal_exception_handler'); // Emit the correct charset HTTP header. drupal_set_header('Content-Type: text/html; charset=utf-8'); // Detect string handling method diff --git includes/database/database.inc includes/database/database.inc index afa772d..cd16695 100644 --- includes/database/database.inc +++ includes/database/database.inc @@ -7,13 +7,6 @@ */ /** - * A hash value to check when outputting database errors, md5('DB_ERROR'). - * - * @see drupal_error_handler() - */ -define('DB_ERROR', 'a515ac9c2796ca0e23adbe92c68fc9fc'); - -/** * @defgroup database Database abstraction layer * @{ * Allow the use of different database servers using the same code base.