OpenSourcery

<?php
// $Id$
 
/**
 * @file
 * Handles incoming requests to fire off regularly-scheduled tasks (cron jobs).
 *
 * The file executes cron hooks selectively, instead of all-or-nothing.
 * This allows cron jobs to be configured with variable frequency.
 * Example usage:
 * * * * * * curl example.com/cron_selective.php?modules=notifications
 * *∕15 * * * * curl example.com/cron_selective.php?modules=aggregator
 * 0 0 * * * curl example.com/cron_selective.php?modules=system,dblog
 *
 */
 
include_once './includes/bootstrap.inc';
drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL);
 
$modules = array_intersect(module_list(), explode(',', $_GET['modules']));
 
drupal_cron_run_selective($modules);
 
/**
 * Executes a cron run when called
 * @return
 * Returns TRUE if ran successfully
 */
function drupal_cron_run_selective($modules) {
  // If not in 'safe mode', increase the maximum execution time:
  if (!ini_get('safe_mode')) {
    set_time_limit(240);
  }
 
  // Fetch the cron semaphore
  $semaphore = variable_get('cron_semaphore', FALSE);
 
  if ($semaphore) {
    if (time() - $semaphore > 3600) {
      // Either cron has been running for more than an hour or the semaphore
      // was not reset due to a database error.
      watchdog('cron', 'Cron has been running for more than an hour and is most likely stuck.', array(), WATCHDOG_ERROR);
 
      // Release cron semaphore
      variable_del('cron_semaphore');
    }
    else {
      // Cron is still running normally.
      watchdog('cron', 'Attempting to re-run cron while it is already running.', array(), WATCHDOG_WARNING);
    }
  }
  else {
    // Register shutdown callback
    register_shutdown_function('drupal_cron_cleanup');
 
    // Lock cron semaphore
    variable_set('cron_semaphore', time());
 
    // Iterate through the modules calling their cron handlers (if any):
    foreach ($modules as $module) {
      module_invoke($module, 'cron');
      watchdog('cron', 'Selective cron run completed for %module.', array('%module' => $module), WATCHDOG_NOTICE);
    }
 
    // Release cron semaphore
    variable_del('cron_semaphore');
  }
}