<?php

/**

 * @file

 * Code required only when fetching information about available updates.

 */

/**

 * Page callback: Checks for updates and displays the update status report.

 *

 * Manually checks the update status without the use of cron.

 *

 * @see update_menu()

 */

function update_manual_status() {

  _update_refresh();

  $batch = array(

    'operations' => array(

      array('update_fetch_data_batch', array()),

    ),

    'finished' => 'update_fetch_data_finished',

    'title' => t('Checking available update data'),

    'progress_message' => t('Trying to check available update data ...'),

    'error_message' => t('Error checking available update data.'),

    'file' => drupal_get_path('module', 'update') . '/update.fetch.inc',

  );

  batch_set($batch);

  batch_process('admin/reports/updates');

}

/**

 * Implements callback_batch_operation().

 *

 * Processes a step in batch for fetching available update data.

 *

 * @param $context

 *   Reference to an array used for Batch API storage.

 */

function update_fetch_data_batch(&$context) {

  $queue = DrupalQueue::get('update_fetch_tasks');

  if (empty($context['sandbox']['max'])) {

    $context['finished'] = 0;

    $context['sandbox']['max'] = $queue->numberOfItems();

    $context['sandbox']['progress'] = 0;

    $context['message'] = t('Checking available update data ...');

    $context['results']['updated'] = 0;

    $context['results']['failures'] = 0;

    $context['results']['processed'] = 0;

  }

  // Grab another item from the fetch queue.

  for ($i = 0; $i < 5; $i++) {

    if ($item = $queue->claimItem()) {

      if (_update_process_fetch_task($item->data)) {

        $context['results']['updated']++;

        $context['message'] = t('Checked available update data for %title.', array('%title' => $item->data['info']['name']));

      }

      else {

        $context['message'] = t('Failed to check available update data for %title.', array('%title' => $item->data['info']['name']));

        $context['results']['failures']++;

      }

      $context['sandbox']['progress']++;

      $context['results']['processed']++;

      $context['finished'] = $context['sandbox']['progress'] / $context['sandbox']['max'];

      $queue->deleteItem($item);

    }

    else {

      // If the queue is currently empty, we're done. It's possible that

      // another thread might have added new fetch tasks while we were

      // processing this batch. In that case, the usual 'finished' math could

      // get confused, since we'd end up processing more tasks that we thought

      // we had when we started and initialized 'max' with numberOfItems(). By

      // forcing 'finished' to be exactly 1 here, we ensure that batch

      // processing is terminated.

      $context['finished'] = 1;

      return;

    }

  }

}

/**

 * Implements callback_batch_finished().

 *

 * Performs actions when all fetch tasks have been completed.

 *

 * @param $success

 *   TRUE if the batch operation was successful; FALSE if there were errors.

 * @param $results

 *   An associative array of results from the batch operation, including the key

 *   'updated' which holds the total number of projects we fetched available

 *   update data for.

 */

function update_fetch_data_finished($success, $results) {

  if ($success) {

    if (!empty($results)) {

      if (!empty($results['updated'])) {

        drupal_set_message(format_plural($results['updated'], 'Checked available update data for one project.', 'Checked available update data for @count projects.'));

      }

      if (!empty($results['failures'])) {

        drupal_set_message(format_plural($results['failures'], 'Failed to get available update data for one project.', 'Failed to get available update data for @count projects.'), 'error');

      }

    }

  }

  else {

    drupal_set_message(t('An error occurred trying to get available update data.'), 'error');

  }

}

/**

 * Attempts to drain the queue of tasks for release history data to fetch.

 */

function _update_fetch_data() {

  $queue = DrupalQueue::get('update_fetch_tasks');

  $end = time() + variable_get('update_max_fetch_time', UPDATE_MAX_FETCH_TIME);

  while (time() < $end && ($item = $queue->claimItem())) {

    _update_process_fetch_task($item->data);

    $queue->deleteItem($item);

  }

}

/**

 * Processes a task to fetch available update data for a single project.

 *

 * Once the release history XML data is downloaded, it is parsed and saved into

 * the {cache_update} table in an entry just for that project.

 *

 * @param $project

 *   Associative array of information about the project to fetch data for.

 *

 * @return

 *   TRUE if we fetched parsable XML, otherwise FALSE.

 */

function _update_process_fetch_task($project) {

  global $base_url;

  $fail = &drupal_static(__FUNCTION__, array());

  // This can be in the middle of a long-running batch, so REQUEST_TIME won't

  // necessarily be valid.

  $now = time();

  if (empty($fail)) {

    // If we have valid data about release history XML servers that we have

    // failed to fetch from on previous attempts, load that from the cache.

    if (($cache = _update_cache_get('fetch_failures')) && ($cache->expire > $now)) {

      $fail = $cache->data;

    }

  }

  $max_fetch_attempts = variable_get('update_max_fetch_attempts', UPDATE_MAX_FETCH_ATTEMPTS);

  $success = FALSE;

  $available = array();

  $site_key = drupal_hmac_base64($base_url, drupal_get_private_key());

  $url = _update_build_fetch_url($project, $site_key);

  $fetch_url_base = _update_get_fetch_url_base($project);

  $project_name = $project['name'];

  if (empty($fail[$fetch_url_base]) || $fail[$fetch_url_base] < $max_fetch_attempts) {

    $xml = drupal_http_request($url);

    if (!isset($xml->error) && isset($xml->data)) {

      $data = $xml->data;

    }

  }

  if (!empty($data)) {

    $available = update_parse_xml($data);

    // @todo: Purge release data we don't need (http://drupal.org/node/238950).

    if (!empty($available)) {

      // Only if we fetched and parsed something sane do we return success.

      $success = TRUE;

    }

  }

  else {

    $available['project_status'] = 'not-fetched';

    if (empty($fail[$fetch_url_base])) {

      $fail[$fetch_url_base] = 1;

    }

    else {

      $fail[$fetch_url_base]++;

    }

  }

  $frequency = variable_get('update_check_frequency', 1);

  $cid = 'available_releases::' . $project_name;

  _update_cache_set($cid, $available, $now + (60 * 60 * 24 * $frequency));

  // Stash the $fail data back in the DB for the next 5 minutes.

  _update_cache_set('fetch_failures', $fail, $now + (60 * 5));

  // Whether this worked or not, we did just (try to) check for updates.

  variable_set('update_last_check', $now);

  // Now that we processed the fetch task for this project, clear out the

  // record in {cache_update} for this task so we're willing to fetch again.

  _update_cache_clear('fetch_task::' . $project_name);

  return $success;

}

/**

 * Clears out all the cached available update data and initiates re-fetching.

 */

function _update_refresh() {

  module_load_include('inc', 'update', 'update.compare');

  // Since we're fetching new available update data, we want to clear

  // our cache of both the projects we care about, and the current update

  // status of the site. We do *not* want to clear the cache of available

  // releases just yet, since that data (even if it's stale) can be useful

  // during update_get_projects(); for example, to modules that implement

  // hook_system_info_alter() such as cvs_deploy.

  _update_cache_clear('update_project_projects');

  _update_cache_clear('update_project_data');

  $projects = update_get_projects();

  // Now that we have the list of projects, we should also clear our cache of

  // available release data, since even if we fail to fetch new data, we need

  // to clear out the stale data at this point.

  _update_cache_clear('available_releases::', TRUE);

  foreach ($projects as $key => $project) {

    update_create_fetch_task($project);

  }

}

/**

 * Adds a task to the queue for fetching release history data for a project.

 *

 * We only create a new fetch task if there's no task already in the queue for

 * this particular project (based on 'fetch_task::' entries in the

 * {cache_update} table).

 *

 * @param $project

 *   Associative array of information about a project as created by

 *   update_get_projects(), including keys such as 'name' (short name), and the

 *   'info' array with data from a .info file for the project.

 *

 * @see update_get_projects()

 * @see update_get_available()

 * @see update_refresh()

 * @see update_fetch_data()

 * @see _update_process_fetch_task()

 */

function _update_create_fetch_task($project) {

  $fetch_tasks = &drupal_static(__FUNCTION__, array());

  if (empty($fetch_tasks)) {

    $fetch_tasks = _update_get_cache_multiple('fetch_task');

  }

  $cid = 'fetch_task::' . $project['name'];

  if (empty($fetch_tasks[$cid])) {

    $queue = DrupalQueue::get('update_fetch_tasks');

    $queue->createItem($project);

    // Due to race conditions, it is possible that another process already

    // inserted a row into the {cache_update} table and the following query will

    // throw an exception.

    // @todo: Remove the need for the manual check by relying on a queue that

    // enforces unique items.

    try {

      db_insert('cache_update')

        ->fields(array(

          'cid' => $cid,

          'created' => REQUEST_TIME,

        ))

        ->execute();

    }

    catch (Exception $e) {

      // The exception can be ignored safely.

    }

    $fetch_tasks[$cid] = REQUEST_TIME;

  }

}

/**

 * Generates the URL to fetch information about project updates.

 *

 * This figures out the right URL to use, based on the project's .info file and

 * the global defaults. Appends optional query arguments when the site is

 * configured to report usage stats.

 *

 * @param $project

 *   The array of project information from update_get_projects().

 * @param $site_key

 *   (optional) The anonymous site key hash. Defaults to an empty string.

 *

 * @return

 *   The URL for fetching information about updates to the specified project.

 *

 * @see update_fetch_data()

 * @see _update_process_fetch_task()

 * @see update_get_projects()

 */

function _update_build_fetch_url($project, $site_key = '') {

  $name = $project['name'];

  $url = _update_get_fetch_url_base($project);

  $url .= '/' . $name . '/' . DRUPAL_CORE_COMPATIBILITY;

  // Only append usage information if we have a site key and the project is

  // enabled. We do not want to record usage statistics for disabled projects.

  if (!empty($site_key) && (strpos($project['project_type'], 'disabled') === FALSE)) {

    // Append the site key.

    $url .= (strpos($url, '?') !== FALSE) ? '&' : '?';

    $url .= 'site_key=';

    $url .= rawurlencode($site_key);

    // Append the version.

    if (!empty($project['info']['version'])) {

      $url .= '&version=';

      $url .= rawurlencode($project['info']['version']);

    }

    // Append the list of modules or themes enabled.

    $list = array_keys($project['includes']);

    $url .= '&list=';

    $url .= rawurlencode(implode(',', $list));

  }

  return $url;

}

/**

 * Returns the base of the URL to fetch available update data for a project.

 *

 * @param $project

 *   The array of project information from update_get_projects().

 *

 * @return

 *   The base of the URL used for fetching available update data. This does

 *   not include the path elements to specify a particular project, version,

 *   site_key, etc.

 *

 * @see _update_build_fetch_url()

 */

function _update_get_fetch_url_base($project) {

  return isset($project['info']['project status url']) ? $project['info']['project status url'] : variable_get('update_fetch_url', UPDATE_DEFAULT_URL);

}

/**

 * Performs any notifications that should be done once cron fetches new data.

 *

 * This method checks the status of the site using the new data and, depending

 * on the configuration of the site, notifies administrators via e-mail if there

 * are new releases or missing security updates.

 *

 * @see update_requirements()

 */

function _update_cron_notify() {

  module_load_install('update');

  $status = update_requirements('runtime');

  $params = array();

  $notify_all = (variable_get('update_notification_threshold', 'all') == 'all');

  foreach (array('core', 'contrib') as $report_type) {

    $type = 'update_' . $report_type;

    if (isset($status[$type]['severity'])

        && ($status[$type]['severity'] == REQUIREMENT_ERROR || ($notify_all && $status[$type]['reason'] == UPDATE_NOT_CURRENT))) {

      $params[$report_type] = $status[$type]['reason'];

    }

  }

  if (!empty($params)) {

    $notify_list = variable_get('update_notify_emails', '');

    if (!empty($notify_list)) {

      $default_language = language_default();

      foreach ($notify_list as $target) {

        if ($target_user = user_load_by_mail($target)) {

          $target_language = user_preferred_language($target_user);

        }

        else {

          $target_language = $default_language;

        }

        $message = drupal_mail('update', 'status_notify', $target, $target_language, $params);

        // Track when the last mail was successfully sent to avoid sending

        // too many e-mails.

        if ($message['result']) {

          variable_set('update_last_email_notification', REQUEST_TIME);

        }

      }

    }

  }

}

/**

 * Parses the XML of the Drupal release history info files.

 *

 * @param $raw_xml

 *   A raw XML string of available release data for a given project.

 *

 * @return

 *   Array of parsed data about releases for a given project, or NULL if there

 *   was an error parsing the string.

 */

function update_parse_xml($raw_xml) {

  try {

    $xml = new SimpleXMLElement($raw_xml);

  }

  catch (Exception $e) {

    // SimpleXMLElement::__construct produces an E_WARNING error message for

    // each error found in the XML data and throws an exception if errors

    // were detected. Catch any exception and return failure (NULL).

    return;

  }

  // If there is no valid project data, the XML is invalid, so return failure.

  if (!isset($xml->short_name)) {

    return;

  }

  $short_name = (string) $xml->short_name;

  $data = array();

  foreach ($xml as $k => $v) {

    $data[$k] = (string) $v;

  }

  $data['releases'] = array();

  if (isset($xml->releases)) {

    foreach ($xml->releases->children() as $release) {

      $version = (string) $release->version;

      $data['releases'][$version] = array();

      foreach ($release->children() as $k => $v) {

        $data['releases'][$version][$k] = (string) $v;

      }

      $data['releases'][$version]['terms'] = array();

      if ($release->terms) {

        foreach ($release->terms->children() as $term) {

          if (!isset($data['releases'][$version]['terms'][(string) $term->name])) {

            $data['releases'][$version]['terms'][(string) $term->name] = array();

          }

          $data['releases'][$version]['terms'][(string) $term->name][] = (string) $term->value;

        }