function cache_clear_all in Memcache API and Integration 5.2

Same name in this branch

1. 5.2 memcache.db.inc \cache_clear_all()
2. 5.2 memcache.inc \cache_clear_all()

Same name and namespace in other branches

1. 5 memcache.db.inc \cache_clear_all()
2. 5 memcache.inc \cache_clear_all()
3. 6 memcache.db.inc \cache_clear_all()
4. 6 memcache.inc \cache_clear_all()

Expire data from the cache. If called without arguments, expirable entries will be cleared from the cache_page table.

Parameters

$cid: If set, the cache ID to delete. Otherwise, all cache entries that can expire are deleted.

$table: If set, the table $table to delete from. Mandatory argument if $cid is set.

$wildcard: If set to TRUE, the $cid is treated as a substring to match rather than a complete ID. The match is a right hand match. If '*' is given as $cid, the table $table will be emptied.

File

./memcache.db.inc, line 165

Code

function cache_clear_all($cid = NULL, $table = NULL, $wildcard = FALSE) {
  global $user;

  // Memcache logic is simpler because memcache doesn't have a minimum cache
  // lifetime consideration (it handles it internally), and doesn't support
  // wildcards.
  $bin = empty($table) ? 'cache' : $table;
  if (empty($cid) || $cid == '*') {
    dmemcache_flush($table);
  }
  else {
    dmemcache_delete($cid, $table);
  }
  if (!isset($cid) && !isset($table)) {
    cache_clear_all(NULL, 'cache_page');
    return;
  }
  if (empty($cid)) {
    if (variable_get('cache_lifetime', 0)) {

      // We store the time in the current user's $user->cache variable which
      // will be saved into the sessions table by sess_write(). We then
      // simulate that the cache was flushed for this user by not returning
      // cached data that was cached before the timestamp.
      $user->cache = time();
      $cache_flush = variable_get('cache_flush', 0);
      if ($cache_flush == 0) {

        // This is the first request to clear the cache, start a timer.
        variable_set('cache_flush', time());
      }
      else {
        if (time() > $cache_flush + variable_get('cache_lifetime', 0)) {

          // Clear the cache for everyone, cache_flush_delay seconds have
          // passed since the first request to clear the cache.
          db_query("DELETE FROM {%s} WHERE expire != %d AND expire < %d", $table, CACHE_PERMANENT, time());
          variable_set('cache_flush', 0);
        }
      }
    }
    else {

      // No minimum cache lifetime, flush all temporary cache entries now.
      db_query("DELETE FROM {%s} WHERE expire != %d AND expire < %d", $table, CACHE_PERMANENT, time());
    }
  }
  else {
    if ($wildcard) {
      if ($cid == '*') {
        db_query("DELETE FROM {%s}", $table);
      }
      else {
        db_query("DELETE FROM {%s} WHERE cid LIKE '%s%%'", $table, $cid);
      }
    }
    else {
      db_query("DELETE FROM {%s} WHERE cid = '%s'", $table, $cid);
    }
  }
}