function cache_get in Drupal 5

Same name and namespace in other branches

1. 4 includes/bootstrap.inc \cache_get()
2. 6 includes/cache.inc \cache_get()
3. 6 includes/cache-install.inc \cache_get()
4. 7 includes/cache.inc \cache_get()

Return data from the persistent cache.

Parameters

$key: The cache ID of the data to retrieve.

$table: The table $table to store the data in. Valid core values are 'cache_filter', 'cache_menu', 'cache_page', or 'cache' for the default cache.

5 calls to cache_get()

check_markup in modules/filter/filter.module

Run all the enabled filters on a piece of text.

locale in modules/locale/locale.module

Provides interface translation services.

menu_get_menu in includes/menu.inc

Return the menu data structure.

page_get_cache in includes/bootstrap.inc

Retrieve the current page from the cache.

variable_init in includes/bootstrap.inc

Load the persistent variable table.

File

includes/cache.inc, line 12

Code

function cache_get($key, $table = 'cache') {
  global $user;

  // Garbage collection necessary when enforcing a minimum cache lifetime
  $cache_flush = variable_get('cache_flush_' . $table, 0);
  if ($cache_flush && $cache_flush + variable_get('cache_lifetime', 0) <= time()) {

    // Reset the variable immediately to prevent a meltdown in heavy load situations.
    variable_set('cache_flush_' . $table, 0);

    // Time to flush old cache data
    db_query("DELETE FROM {" . $table . "} WHERE expire != %d AND expire <= %d", CACHE_PERMANENT, $cache_flush);
  }
  $cache = db_fetch_object(db_query("SELECT data, created, headers, expire FROM {" . $table . "} WHERE cid = '%s'", $key));
  if (isset($cache->data)) {

    // If the data is permanent or we're not enforcing a minimum cache lifetime
    // always return the cached data.
    if ($cache->expire == CACHE_PERMANENT || !variable_get('cache_lifetime', 0)) {
      $cache->data = db_decode_blob($cache->data);
    }
    else {
      if ($user->cache > $cache->created) {

        // This cache data is too old and thus not valid for us, ignore it.
        return 0;
      }
      else {
        $cache->data = db_decode_blob($cache->data);
      }
    }
    return $cache;
  }
  return 0;
}