function _drupal_log_error

Logs a PHP error or exception and displays an error page in fatal cases.

Parameters

$error: An array with the following keys: %type, !message, %function, %file, %line, severity_level, and backtrace. All the parameters are plain-text, with the exception of !message, which needs to be a safe HTML string, and backtrace, which is a standard PHP backtrace.

$fatal: TRUE if the error is fatal.

File

drupal/core/includes/errors.inc, line 177

Functions for error handling.

Code

function _drupal_log_error($error, $fatal = FALSE) {

  // Initialize a maintenance theme if the boostrap was not complete.
  // Do it early because drupal_set_message() triggers a drupal_theme_initialize().
  if ($fatal && drupal_get_bootstrap_phase() != DRUPAL_BOOTSTRAP_FULL) {
    unset($GLOBALS['theme']);
    if (!defined('MAINTENANCE_MODE')) {
      define('MAINTENANCE_MODE', 'error');
    }
    drupal_maintenance_theme();
  }

  // Backtrace array is not a valid replacement value for t().
  $backtrace = $error['backtrace'];
  unset($error['backtrace']);

  // When running inside the testing framework, we relay the errors
  // to the tested site by the way of HTTP headers.
  $test_info =& $GLOBALS['drupal_test_info'];
  if (!empty($test_info['in_child_site']) && !headers_sent() && (!defined('SIMPLETEST_COLLECT_ERRORS') || SIMPLETEST_COLLECT_ERRORS)) {

    // $number does not use drupal_static as it should not be reset
    // as it uniquely identifies each PHP error.
    static $number = 0;
    $assertion = array(
      $error['!message'],
      $error['%type'],
      array(
        'function' => $error['%function'],
        'file' => $error['%file'],
        'line' => $error['%line'],
      ),
    );
    header('X-Drupal-Assertion-' . $number . ': ' . rawurlencode(serialize($assertion)));
    $number++;
  }
  watchdog('php', '%type: !message in %function (line %line of %file).', $error, $error['severity_level']);
  if (drupal_is_cli()) {
    if ($fatal) {

      // When called from CLI, simply output a plain text message.
      // Should not translate the string to avoid errors producing more errors.
      print html_entity_decode(strip_tags(format_string('%type: !message in %function (line %line of %file).', $error))) . "\n";
      exit;
    }
  }
  if (isset($_SERVER['HTTP_X_REQUESTED_WITH']) && $_SERVER['HTTP_X_REQUESTED_WITH'] == 'XMLHttpRequest') {
    if ($fatal) {
      if (error_displayable($error)) {

        // When called from JavaScript, simply output the error message.
        // Should not translate the string to avoid errors producing more errors.
        print format_string('%type: !message in %function (line %line of %file).', $error);
      }
      exit;
    }
  }
  else {

    // Display the message if the current error reporting level allows this type
    // of message to be displayed, and unconditionnaly in update.php.
    if (error_displayable($error)) {
      $class = 'error';

      // If error type is 'User notice' then treat it as debug information
      // instead of an error message.
      // @see debug()
      if ($error['%type'] == 'User notice') {
        $error['%type'] = 'Debug';
        $class = 'status';
      }

      // Attempt to reduce verbosity by removing DRUPAL_ROOT from the file path
      // in the message. This does not happen for (false) security.
      $root_length = strlen(DRUPAL_ROOT);
      if (substr($error['%file'], 0, $root_length) == DRUPAL_ROOT) {
        $error['%file'] = substr($error['%file'], $root_length + 1);
      }

      // Should not translate the string to avoid errors producing more errors.
      $message = format_string('%type: !message in %function (line %line of %file).', $error);

      // Check if verbose error reporting is on.
      $error_level = config('system.logging')
        ->get('error_level');
      if ($error_level == ERROR_REPORTING_DISPLAY_VERBOSE) {

        // First trace is the error itself, already contained in the message.
        // While the second trace is the error source and also contained in the
        // message, the message doesn't contain argument values, so we output it
        // once more in the backtrace.
        array_shift($backtrace);

        // Generate a backtrace containing only scalar argument values.
        $message .= '<pre class="backtrace">' . format_backtrace($backtrace) . '</pre>';
      }
      drupal_set_message($message, $class, TRUE);
    }
    if ($fatal) {

      // Should not translate the string to avoid errors producing more errors.
      drupal_set_title('Error');

      // We fallback to a maintenance page at this point, because the page generation
      // itself can generate errors.
      // Should not translate the string to avoid errors producing more errors.
      $output = theme('maintenance_page', array(
        'content' => 'The website has encountered an error. Please try again later.',
      ));
      $response = new Response($output, 500);
      if ($fatal) {
        $response
          ->setStatusCode(500, '500 Service unavailable (with message)');
      }
      return $response;
    }
  }
}