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Drupal example source code file (update.compare.inc)

This example Drupal source code file (update.compare.inc) is included in the DevDaily.com "Drupal Source Code Warehouse" project. The intent of this project is to help you "Learn Drupal by Example".

PHP - Drupal tags/keywords

array, available, elseif, empty, foreach, function, if, isset, php, projects, release, return, update, variable

The update.compare.inc Drupal example source code

<?php
// $Id: update.compare.inc,v 1.41 2010/10/04 07:26:25 webchick Exp $

/**
 * @file
 * Code required only when comparing available updates to existing data.
 */

/**
 * Fetch an array of installed and enabled projects.
 *
 * This is only responsible for generating an array of projects (taking into
 * account projects that include more than one module or theme). Other
 * information like the specific version and install type (official release,
 * dev snapshot, etc) is handled later in update_process_project_info() since
 * that logic is only required when preparing the status report, not for
 * fetching the available release data.
 *
 * This array is fairly expensive to construct, since it involves a lot of
 * disk I/O, so we cache the results into the {cache_update} table using the
 * 'update_project_projects' cache ID. However, since this is not the data
 * about available updates fetched from the network, it is ok to invalidate it
 * somewhat quickly. If we keep this data for very long, site administrators
 * are more likely to see incorrect results if they upgrade to a newer version
 * of a module or theme but do not visit certain pages that automatically
 * clear this cache.
 *
 * @see update_process_project_info()
 * @see update_calculate_project_data()
 * @see update_project_cache()
 */
function update_get_projects() {
  $projects = &drupal_static(__FUNCTION__, array());
  if (empty($projects)) {
    // Retrieve the projects from cache, if present.
    $projects = update_project_cache('update_project_projects');
    if (empty($projects)) {
      // Still empty, so we have to rebuild the cache.
      $module_data = system_rebuild_module_data();
      $theme_data = system_rebuild_theme_data();
      _update_process_info_list($projects, $module_data, 'module', TRUE);
      _update_process_info_list($projects, $theme_data, 'theme', TRUE);
      if (variable_get('update_check_disabled', FALSE)) {
        _update_process_info_list($projects, $module_data, 'module', FALSE);
        _update_process_info_list($projects, $theme_data, 'theme', FALSE);
      }
      // Allow other modules to alter projects before fetching and comparing.
      drupal_alter('update_projects', $projects);
      // Cache the site's project data for at most 1 hour.
      _update_cache_set('update_project_projects', $projects, REQUEST_TIME + 3600);
    }
  }
  return $projects;
}

/**
 * Populate an array of project data.
 *
 * This iterates over a list of the installed modules or themes and groups
 * them by project and status. A few parts of this function assume that
 * enabled modules and themes are always processed first, and if disabled
 * modules or themes are being processed (there is a setting to control if
 * disabled code should be included in the Available updates report or not),
 * those are only processed after $projects has been populated with
 * information about the enabled code. 'Hidden' modules and themes are always
 * ignored. This function also records the latest change time on the .info
 * files for each module or theme, which is important data which is used when
 * deciding if the cached available update data should be invalidated.
 *
 * @param $projects
 *   Reference to the array of project data of what's installed on this site.
 * @param $list
 *   Array of data to process to add the relevant info to the $projects array.
 * @param $project_type
 *   The kind of data in the list (can be 'module' or 'theme').
 * @param $status
 *   Boolean that controls what status (enabled or disabled) to process out of
 *   the $list and add to the $projects array.
 *
 * @see update_get_projects()
 */
function _update_process_info_list(&$projects, $list, $project_type, $status) {
  foreach ($list as $file) {
    // A disabled base theme of an enabled sub-theme still has all of its code
    // run by the sub-theme, so we include it in our "enabled" projects list.
    if ($status && !$file->status && !empty($file->sub_themes)) {
      foreach ($file->sub_themes as $key => $name) {
        // Build a list of enabled sub-themes.
        if ($list[$key]->status) {
          $file->enabled_sub_themes[$key] = $name;
        }
      }
      // If there are no enabled subthemes, we should ignore this base theme
      // for the enabled case. If the site is trying to display disabled
      // themes, we'll catch it then.
      if (empty($file->enabled_sub_themes)) {
        continue;
      }
    }
    // Otherwise, just add projects of the proper status to our list.
    elseif ($file->status != $status) {
      continue;
    }

    // Skip if the .info file is broken.
    if (empty($file->info)) {
      continue;
    }

    // Skip if it's a hidden module or theme.
    if (!empty($file->info['hidden'])) {
      continue;
    }

    // If the .info doesn't define the 'project', try to figure it out.
    if (!isset($file->info['project'])) {
      $file->info['project'] = update_get_project_name($file);
    }

    // If we still don't know the 'project', give up.
    if (empty($file->info['project'])) {
      continue;
    }

    // If we don't already know it, grab the change time on the .info file
    // itself. Note: we need to use the ctime, not the mtime (modification
    // time) since many (all?) tar implementations will go out of their way to
    // set the mtime on the files it creates to the timestamps recorded in the
    // tarball. We want to see the last time the file was changed on disk,
    // which is left alone by tar and correctly set to the time the .info file
    // was unpacked.
    if (!isset($file->info['_info_file_ctime'])) {
      $info_filename = dirname($file->uri) . '/' . $file->name . '.info';
      $file->info['_info_file_ctime'] = filectime($info_filename);
    }

    if (!isset($file->info['datestamp'])) {
      $file->info['datestamp'] = 0;
    }

    $project_name = $file->info['project'];

    // Figure out what project type we're going to use to display this module
    // or theme. If the project name is 'drupal', we don't want it to show up
    // under the usual "Modules" section, we put it at a special "Drupal Core"
    // section at the top of the report.
    if ($project_name == 'drupal') {
      $project_display_type = 'core';
    }
    else {
      $project_display_type = $project_type;
    }
    if (empty($status) && empty($file->enabled_sub_themes)) {
      // If we're processing disabled modules or themes, append a suffix.
      // However, we don't do this to a a base theme with enabled
      // subthemes, since we treat that case as if it is enabled.
      $project_display_type .= '-disabled';
    }
    // Add a list of sub-themes that "depend on" the project and a list of base
    // themes that are "required by" the project.
    if ($project_name == 'drupal') {
      // Drupal core is always required, so this extra info would be noise.
      $sub_themes = array();
      $base_themes = array();
    }
    else {
      // Add list of enabled sub-themes.
      $sub_themes = !empty($file->enabled_sub_themes) ? $file->enabled_sub_themes : array();
      // Add list of base themes.
      $base_themes = !empty($file->base_themes) ? $file->base_themes : array();
    }
    if (!isset($projects[$project_name])) {
      // Only process this if we haven't done this project, since a single
      // project can have multiple modules or themes.
      $projects[$project_name] = array(
        'name' => $project_name,
        // Only save attributes from the .info file we care about so we do not
        // bloat our RAM usage needlessly.
        'info' => update_filter_project_info($file->info),
        'datestamp' => $file->info['datestamp'],
        'includes' => array($file->name => $file->info['name']),
        'project_type' => $project_display_type,
        'project_status' => $status,
        'sub_themes' => $sub_themes,
        'base_themes' => $base_themes,
      );
    }
    elseif ($projects[$project_name]['project_type'] == $project_display_type) {
      // Only add the file we're processing to the 'includes' array for this
      // project if it is of the same type and status (which is encoded in the
      // $project_display_type). This prevents listing all the disabled
      // modules included with an enabled project if we happen to be checking
      // for disabled modules, too.
      $projects[$project_name]['includes'][$file->name] = $file->info['name'];
      $projects[$project_name]['info']['_info_file_ctime'] = max($projects[$project_name]['info']['_info_file_ctime'], $file->info['_info_file_ctime']);
      $projects[$project_name]['datestamp'] = max($projects[$project_name]['datestamp'], $file->info['datestamp']);
      if (!empty($sub_themes)) {
        $projects[$project_name]['sub_themes'] += $sub_themes;
      }
      if (!empty($base_themes)) {
        $projects[$project_name]['base_themes'] += $base_themes;
      }
    }
    elseif (empty($status)) {
      // If we have a project_name that matches, but the project_display_type
      // does not, it means we're processing a disabled module or theme that
      // belongs to a project that has some enabled code. In this case, we add
      // the disabled thing into a separate array for separate display.
      $projects[$project_name]['disabled'][$file->name] = $file->info['name'];
    }
  }
}

/**
 * Given a $file object (as returned by system_get_files_database()), figure
 * out what project it belongs to.
 *
 * @see system_get_files_database()
 */
function update_get_project_name($file) {
  $project_name = '';
  if (isset($file->info['project'])) {
    $project_name = $file->info['project'];
  }
  elseif (isset($file->info['package']) && (strpos($file->info['package'], 'Core') === 0)) {
    $project_name = 'drupal';
  }
  return $project_name;
}

/**
 * Process the list of projects on the system to figure out the currently
 * installed versions, and other information that is required before we can
 * compare against the available releases to produce the status report.
 *
 * @param $projects
 *   Array of project information from update_get_projects().
 */
function update_process_project_info(&$projects) {
  foreach ($projects as $key => $project) {
    // Assume an official release until we see otherwise.
    $install_type = 'official';

    $info = $project['info'];

    if (isset($info['version'])) {
      // Check for development snapshots
      if (preg_match('@(dev|HEAD)@', $info['version'])) {
        $install_type = 'dev';
      }

      // Figure out what the currently installed major version is. We need
      // to handle both contribution (e.g. "5.x-1.3", major = 1) and core
      // (e.g. "5.1", major = 5) version strings.
      $matches = array();
      if (preg_match('/^(\d+\.x-)?(\d+)\..*$/', $info['version'], $matches)) {
        $info['major'] = $matches[2];
      }
      elseif (!isset($info['major'])) {
        // This would only happen for version strings that don't follow the
        // drupal.org convention. We let contribs define "major" in their
        // .info in this case, and only if that's missing would we hit this.
        $info['major'] = -1;
      }
    }
    else {
      // No version info available at all.
      $install_type = 'unknown';
      $info['version'] = t('Unknown');
      $info['major'] = -1;
    }

    // Finally, save the results we care about into the $projects array.
    $projects[$key]['existing_version'] = $info['version'];
    $projects[$key]['existing_major'] = $info['major'];
    $projects[$key]['install_type'] = $install_type;
  }
}

/**
 * Calculate the current update status of all projects on the site.
 *
 * The results of this function are expensive to compute, especially on sites
 * with lots of modules or themes, since it involves a lot of comparisons and
 * other operations. Therefore, we cache the results into the {cache_update}
 * table using the 'update_project_data' cache ID. However, since this is not
 * the data about available updates fetched from the network, it is ok to
 * invalidate it somewhat quickly. If we keep this data for very long, site
 * administrators are more likely to see incorrect results if they upgrade to
 * a newer version of a module or theme but do not visit certain pages that
 * automatically clear this cache.
 *
 * @param array $available
 *   Data about available project releases.
 *
 * @see update_get_available()
 * @see update_get_projects()
 * @see update_process_project_info()
 * @see update_project_cache()
 */
function update_calculate_project_data($available) {
  // Retrieve the projects from cache, if present.
  $projects = update_project_cache('update_project_data');
  // If $projects is empty, then the cache must be rebuilt.
  // Otherwise, return the cached data and skip the rest of the function.
  if (!empty($projects)) {
    return $projects;
  }
  $projects = update_get_projects();
  update_process_project_info($projects);
  foreach ($projects as $project => $project_info) {
    if (isset($available[$project])) {
      update_calculate_project_update_status($project, $projects[$project], $available[$project]);
    }
    else {
      $projects[$project]['status'] = UPDATE_UNKNOWN;
      $projects[$project]['reason'] = t('No available releases found');
    }
  }
  // Give other modules a chance to alter the status (for example, to allow a
  // contrib module to provide fine-grained settings to ignore specific
  // projects or releases).
  drupal_alter('update_status', $projects);

  // Cache the site's update status for at most 1 hour.
  _update_cache_set('update_project_data', $projects, REQUEST_TIME + 3600);
  return $projects;
}

/**
 * Calculate the current update status of a specific project.
 *
 * This function is the heart of the update status feature. For each project
 * it is invoked with, it first checks if the project has been flagged with a
 * special status like "unsupported" or "insecure", or if the project node
 * itself has been unpublished. In any of those cases, the project is marked
 * with an error and the next project is considered.
 *
 * If the project itself is valid, the function decides what major release
 * series to consider. The project defines what the currently supported major
 * versions are for each version of core, so the first step is to make sure
 * the current version is still supported. If so, that's the target version.
 * If the current version is unsupported, the project maintainer's recommended
 * major version is used. There's also a check to make sure that this function
 * never recommends an earlier release than the currently installed major
 * version.
 *
 * Given a target major version, it scans the available releases looking for
 * the specific release to recommend (avoiding beta releases and development
 * snapshots if possible). This is complicated to describe, but an example
 * will help clarify. For the target major version, find the highest patch
 * level. If there is a release at that patch level with no extra ("beta",
 * etc), then we recommend the release at that patch level with the most
 * recent release date. If every release at that patch level has extra (only
 * betas), then recommend the latest release from the previous patch
 * level. For example:
 *
 * 1.6-bugfix <-- recommended version because 1.6 already exists.
 * 1.6
 *
 * or
 *
 * 1.6-beta
 * 1.5 <-- recommended version because no 1.6 exists.
 * 1.4
 *
 * It also looks for the latest release from the same major version, even a
 * beta release, to display to the user as the "Latest version" option.
 * Additionally, it finds the latest official release from any higher major
 * versions that have been released to provide a set of "Also available"
 * options.
 *
 * Finally, and most importantly, it keeps scanning the release history until
 * it gets to the currently installed release, searching for anything marked
 * as a security update. If any security updates have been found between the
 * recommended release and the installed version, all of the releases that
 * included a security fix are recorded so that the site administrator can be
 * warned their site is insecure, and links pointing to the release notes for
 * each security update can be included (which, in turn, will link to the
 * official security announcements for each vulnerability).
 *
 * This function relies on the fact that the .xml release history data comes
 * sorted based on major version and patch level, then finally by release date
 * if there are multiple releases such as betas from the same major.patch
 * version (e.g. 5.x-1.5-beta1, 5.x-1.5-beta2, and 5.x-1.5). Development
 * snapshots for a given major version are always listed last.
 *
 */
function update_calculate_project_update_status($project, &$project_data, $available) {
  foreach (array('title', 'link') as $attribute) {
    if (!isset($project_data[$attribute]) && isset($available[$attribute])) {
      $project_data[$attribute] = $available[$attribute];
    }
  }

  // If the project status is marked as something bad, there's nothing else
  // to consider.
  if (isset($available['project_status'])) {
    switch ($available['project_status']) {
      case 'insecure':
        $project_data['status'] = UPDATE_NOT_SECURE;
        if (empty($project_data['extra'])) {
          $project_data['extra'] = array();
        }
        $project_data['extra'][] = array(
          'class' => array('project-not-secure'),
          'label' => t('Project not secure'),
          'data' => t('This project has been labeled insecure by the Drupal security team, and is no longer available for download. Immediately disabling everything included by this project is strongly recommended!'),
        );
        break;
      case 'unpublished':
      case 'revoked':
        $project_data['status'] = UPDATE_REVOKED;
        if (empty($project_data['extra'])) {
          $project_data['extra'] = array();
        }
        $project_data['extra'][] = array(
          'class' => array('project-revoked'),
          'label' => t('Project revoked'),
          'data' => t('This project has been revoked, and is no longer available for download. Disabling everything included by this project is strongly recommended!'),
        );
        break;
      case 'unsupported':
        $project_data['status'] = UPDATE_NOT_SUPPORTED;
        if (empty($project_data['extra'])) {
          $project_data['extra'] = array();
        }
        $project_data['extra'][] = array(
          'class' => array('project-not-supported'),
          'label' => t('Project not supported'),
          'data' => t('This project is no longer supported, and is no longer available for download. Disabling everything included by this project is strongly recommended!'),
        );
        break;
      case 'not-fetched':
        $project_data['status'] = UPDATE_NOT_FETCHED;
        $project_data['reason'] = t('Failed to get available update data.');
        break;

      default:
        // Assume anything else (e.g. 'published') is valid and we should
        // perform the rest of the logic in this function.
        break;
    }
  }

  if (!empty($project_data['status'])) {
    // We already know the status for this project, so there's nothing else to
    // compute. Record the project status into $project_data and we're done.
    $project_data['project_status'] = $available['project_status'];
    return;
  }

  // Figure out the target major version.
  $existing_major = $project_data['existing_major'];
  $supported_majors = array();
  if (isset($available['supported_majors'])) {
    $supported_majors = explode(',', $available['supported_majors']);
  }
  elseif (isset($available['default_major'])) {
    // Older release history XML file without supported or recommended.
    $supported_majors[] = $available['default_major'];
  }

  if (in_array($existing_major, $supported_majors)) {
    // Still supported, stay at the current major version.
    $target_major = $existing_major;
  }
  elseif (isset($available['recommended_major'])) {
    // Since 'recommended_major' is defined, we know this is the new XML
    // format. Therefore, we know the current release is unsupported since
    // its major version was not in the 'supported_majors' list. We should
    // find the best release from the recommended major version.
    $target_major = $available['recommended_major'];
    $project_data['status'] = UPDATE_NOT_SUPPORTED;
  }
  elseif (isset($available['default_major'])) {
    // Older release history XML file without recommended, so recommend
    // the currently defined "default_major" version.
    $target_major = $available['default_major'];
  }
  else {
    // Malformed XML file? Stick with the current version.
    $target_major = $existing_major;
  }

  // Make sure we never tell the admin to downgrade. If we recommended an
  // earlier version than the one they're running, they'd face an
  // impossible data migration problem, since Drupal never supports a DB
  // downgrade path. In the unfortunate case that what they're running is
  // unsupported, and there's nothing newer for them to upgrade to, we
  // can't print out a "Recommended version", but just have to tell them
  // what they have is unsupported and let them figure it out.
  $target_major = max($existing_major, $target_major);

  $release_patch_changed = '';
  $patch = '';

  // If the project is marked as UPDATE_FETCH_PENDING, it means that the
  // data we currently have (if any) is stale, and we've got a task queued
  // up to (re)fetch the data. In that case, we mark it as such, merge in
  // whatever data we have (e.g. project title and link), and move on.
  if (!empty($available['fetch_status']) && $available['fetch_status'] == UPDATE_FETCH_PENDING) {
    $project_data['status'] = UPDATE_FETCH_PENDING;
    $project_data['reason'] = t('No available update data');
    $project_data['fetch_status'] = $available['fetch_status'];
    return;
  }

  // Defend ourselves from XML history files that contain no releases.
  if (empty($available['releases'])) {
    $project_data['status'] = UPDATE_UNKNOWN;
    $project_data['reason'] = t('No available releases found');
    return;
  }
  foreach ($available['releases'] as $version => $release) {
    // First, if this is the existing release, check a few conditions.
    if ($project_data['existing_version'] === $version) {
      if (isset($release['terms']['Release type']) &&
          in_array('Insecure', $release['terms']['Release type'])) {
        $project_data['status'] = UPDATE_NOT_SECURE;
      }
      elseif ($release['status'] == 'unpublished') {
        $project_data['status'] = UPDATE_REVOKED;
        if (empty($project_data['extra'])) {
          $project_data['extra'] = array();
        }
        $project_data['extra'][] = array(
          'class' => array('release-revoked'),
          'label' => t('Release revoked'),
          'data' => t('Your currently installed release has been revoked, and is no longer available for download. Disabling everything included in this release or upgrading is strongly recommended!'),
        );
      }
      elseif (isset($release['terms']['Release type']) &&
              in_array('Unsupported', $release['terms']['Release type'])) {
        $project_data['status'] = UPDATE_NOT_SUPPORTED;
        if (empty($project_data['extra'])) {
          $project_data['extra'] = array();
        }
        $project_data['extra'][] = array(
          'class' => array('release-not-supported'),
          'label' => t('Release not supported'),
          'data' => t('Your currently installed release is now unsupported, and is no longer available for download. Disabling everything included in this release or upgrading is strongly recommended!'),
        );
      }
    }

    // Otherwise, ignore unpublished, insecure, or unsupported releases.
    if ($release['status'] == 'unpublished' ||
        (isset($release['terms']['Release type']) &&
         (in_array('Insecure', $release['terms']['Release type']) ||
          in_array('Unsupported', $release['terms']['Release type'])))) {
      continue;
    }

    // See if this is a higher major version than our target and yet still
    // supported. If so, record it as an "Also available" release.
    if ($release['version_major'] > $target_major) {
      if (in_array($release['version_major'], $supported_majors)) {
        if (!isset($project_data['also'])) {
          $project_data['also'] = array();
        }
        if (!isset($project_data['also'][$release['version_major']])) {
          $project_data['also'][$release['version_major']] = $version;
          $project_data['releases'][$version] = $release;
        }
      }
      // Otherwise, this release can't matter to us, since it's neither
      // from the release series we're currently using nor the recommended
      // release. We don't even care about security updates for this
      // branch, since if a project maintainer puts out a security release
      // at a higher major version and not at the lower major version,
      // they must remove the lower version from the supported major
      // versions at the same time, in which case we won't hit this code.
      continue;
    }

    // Look for the 'latest version' if we haven't found it yet. Latest is
    // defined as the most recent version for the target major version.
    if (!isset($project_data['latest_version'])
        && $release['version_major'] == $target_major) {
      $project_data['latest_version'] = $version;
      $project_data['releases'][$version] = $release;
    }

    // Look for the development snapshot release for this branch.
    if (!isset($project_data['dev_version'])
        && $release['version_major'] == $target_major
        && isset($release['version_extra'])
        && $release['version_extra'] == 'dev') {
      $project_data['dev_version'] = $version;
      $project_data['releases'][$version] = $release;
    }

    // Look for the 'recommended' version if we haven't found it yet (see
    // phpdoc at the top of this function for the definition).
    if (!isset($project_data['recommended'])
        && $release['version_major'] == $target_major
        && isset($release['version_patch'])) {
      if ($patch != $release['version_patch']) {
        $patch = $release['version_patch'];
        $release_patch_changed = $release;
      }
      if (empty($release['version_extra']) && $patch == $release['version_patch']) {
        $project_data['recommended'] = $release_patch_changed['version'];
        $project_data['releases'][$release_patch_changed['version']] = $release_patch_changed;
      }
    }

    // Stop searching once we hit the currently installed version.
    if ($project_data['existing_version'] === $version) {
      break;
    }

    // If we're running a dev snapshot and have a timestamp, stop
    // searching for security updates once we hit an official release
    // older than what we've got. Allow 100 seconds of leeway to handle
    // differences between the datestamp in the .info file and the
    // timestamp of the tarball itself (which are usually off by 1 or 2
    // seconds) so that we don't flag that as a new release.
    if ($project_data['install_type'] == 'dev') {
      if (empty($project_data['datestamp'])) {
        // We don't have current timestamp info, so we can't know.
        continue;
      }
      elseif (isset($release['date']) && ($project_data['datestamp'] + 100 > $release['date'])) {
        // We're newer than this, so we can skip it.
        continue;
      }
    }

    // See if this release is a security update.
    if (isset($release['terms']['Release type'])
        && in_array('Security update', $release['terms']['Release type'])) {
      $project_data['security updates'][] = $release;
    }
  }

  // If we were unable to find a recommended version, then make the latest
  // version the recommended version if possible.
  if (!isset($project_data['recommended']) && isset($project_data['latest_version'])) {
    $project_data['recommended'] = $project_data['latest_version'];
  }

  //
  // Check to see if we need an update or not.
  //

  if (!empty($project_data['security updates'])) {
    // If we found security updates, that always trumps any other status.
    $project_data['status'] = UPDATE_NOT_SECURE;
  }

  if (isset($project_data['status'])) {
    // If we already know the status, we're done.
    return;
  }

  // If we don't know what to recommend, there's nothing we can report.
  // Bail out early.
  if (!isset($project_data['recommended'])) {
    $project_data['status'] = UPDATE_UNKNOWN;
    $project_data['reason'] = t('No available releases found');
    return;
  }

  // If we're running a dev snapshot, compare the date of the dev snapshot
  // with the latest official version, and record the absolute latest in
  // 'latest_dev' so we can correctly decide if there's a newer release
  // than our current snapshot.
  if ($project_data['install_type'] == 'dev') {
    if (isset($project_data['dev_version']) && $available['releases'][$project_data['dev_version']]['date'] > $available['releases'][$project_data['latest_version']]['date']) {
      $project_data['latest_dev'] = $project_data['dev_version'];
    }
    else {
      $project_data['latest_dev'] = $project_data['latest_version'];
    }
  }

  // Figure out the status, based on what we've seen and the install type.
  switch ($project_data['install_type']) {
    case 'official':
      if ($project_data['existing_version'] === $project_data['recommended'] || $project_data['existing_version'] === $project_data['latest_version']) {
        $project_data['status'] = UPDATE_CURRENT;
      }
      else {
        $project_data['status'] = UPDATE_NOT_CURRENT;
      }
      break;

    case 'dev':
      $latest = $available['releases'][$project_data['latest_dev']];
      if (empty($project_data['datestamp'])) {
        $project_data['status'] = UPDATE_NOT_CHECKED;
        $project_data['reason'] = t('Unknown release date');
      }
      elseif (($project_data['datestamp'] + 100 > $latest['date'])) {
        $project_data['status'] = UPDATE_CURRENT;
      }
      else {
        $project_data['status'] = UPDATE_NOT_CURRENT;
      }
      break;

    default:
      $project_data['status'] = UPDATE_UNKNOWN;
      $project_data['reason'] = t('Invalid info');
  }
}

/**
 * Retrieve data from {cache_update} or empty the cache when necessary.
 *
 * Two very expensive arrays computed by this module are the list of all
 * installed modules and themes (and .info data, project associations, etc),
 * and the current status of the site relative to the currently available
 * releases. These two arrays are cached in the {cache_update} table and used
 * whenever possible. The cache is cleared whenever the administrator visits
 * the status report, available updates report, or the module or theme
 * administration pages, since we should always recompute the most current
 * values on any of those pages.
 *
 * Note: while both of these arrays are expensive to compute (in terms of disk
 * I/O and some fairly heavy CPU processing), neither of these is the actual
 * data about available updates that we have to fetch over the network from
 * updates.drupal.org. That information is stored with the
 * 'update_available_releases' cache ID -- it needs to persist longer than 1
 * hour and never get invalidated just by visiting a page on the site.
 *
 * @param $cid
 *   The cache id of data to return from the cache. Valid options are
 *   'update_project_data' and 'update_project_projects'.
 *
 * @return
 *   The cached value of the $projects array generated by
 *   update_calculate_project_data() or update_get_projects(), or an empty
 *   array when the cache is cleared.
 */
function update_project_cache($cid) {
  $projects = array();

  // On certain paths, we should clear the cache and recompute the projects for
  // update status of the site to avoid presenting stale information.
  $q = $_GET['q'];
  $paths = array(
    'admin/modules',
    'admin/modules/update',
    'admin/appearance',
    'admin/appearance/update',
    'admin/reports',
    'admin/reports/updates',
    'admin/reports/updates/update',
    'admin/reports/status',
    'admin/reports/updates/check',
  );
  if (in_array($q, $paths)) {
    _update_cache_clear($cid);
  }
  else {
    $cache = _update_cache_get($cid);
    if (!empty($cache->data) && $cache->expire > REQUEST_TIME) {
      $projects = $cache->data;
    }
  }
  return $projects;
}

/**
 * Filter the project .info data to only save attributes we need.
 *
 * @param array $info
 *   Array of .info file data as returned by drupal_parse_info_file().
 *
 * @return
 *   Array of .info file data we need for the Update manager.
 *
 * @see _update_process_info_list()
 */
function update_filter_project_info($info) {
  $whitelist = array(
    '_info_file_ctime',
    'datestamp',
    'major',
    'name',
    'package',
    'project',
    'project status url',
    'version',
  );
  return array_intersect_key($info, drupal_map_assoc($whitelist));
}

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