drupal/includes/cache-install.inc

<?php
// $Id: cache-install.inc,v 1.5 2009/09/13 17:49:51 dries Exp $

/**
 * A stub cache implementation to be used during the installation
 * process when database access is not yet available. Because Drupal's
 * caching system never requires that cached data be present, these
 * stub functions can short-circuit the process and sidestep the
 * need for any persistent storage. Obviously, using this cache
 * implementation during normal operations would have a negative impact
 * on performance.
 */
class DrupalFakeCache extends DrupalDatabaseCache implements DrupalCacheInterface {
  function get($cid) {
    return FALSE;
  }

  function getMultiple(&$cids) {
    return array();
  }

  function set($cid, $data, $expire = CACHE_PERMANENT, array $headers = NULL) {
  }

  function clear($cid = NULL, $wildcard = FALSE) {
    // If there is a database cache, attempt to clear it whenever possible. The
    // reason for doing this is that the database cache can accumulate data
    // during installation due to any full bootstraps that may occur at the
    // same time (for example, AJAX requests triggered by the installer). If we
    // didn't try to clear it whenever this function is called, the data in the
    // cache would become stale; for example, the installer sometimes calls
    // variable_set(), which updates the {variable} table and then clears the
    // cache to make sure that the next page request picks up the new value.
    // Not actually clearing the cache here therefore leads old variables to be
    // loaded on the first page requests after installation, which can cause
    // subtle bugs, some of which would not be fixed unless the site
    // administrator cleared the cache manually.
    try {
      if (function_exists('drupal_install_initialize_database')) {
        drupal_install_initialize_database();
        parent::clear($cid, $wildcard);
      }
    }
    // If the attempt at clearing the cache causes an error, that means that
    // either the database connection is not set up yet or the relevant cache
    // table in the database has not yet been created, so we can safely do
    // nothing here.
    catch (Exception $e) {
    }
  }

  function isEmpty() {
    return TRUE;
  }
}
1	<?php
2	// $Id: cache-install.inc,v 1.5 2009/09/13 17:49:51 dries Exp $
3
4	/**
5	* A stub cache implementation to be used during the installation
6	* process when database access is not yet available. Because Drupal's
7	* caching system never requires that cached data be present, these
8	* stub functions can short-circuit the process and sidestep the
9	* need for any persistent storage. Obviously, using this cache
10	* implementation during normal operations would have a negative impact
11	* on performance.
12	*/
13	class DrupalFakeCache extends DrupalDatabaseCache implements DrupalCacheInterface {
14	function get($cid) {
15	return FALSE;
16	}
17
18	function getMultiple(&$cids) {
19	return array();
20	}
21
22	function set($cid, $data, $expire = CACHE_PERMANENT, array $headers = NULL) {
23	}
24
25	function clear($cid = NULL, $wildcard = FALSE) {
26	// If there is a database cache, attempt to clear it whenever possible. The
27	// reason for doing this is that the database cache can accumulate data
28	// during installation due to any full bootstraps that may occur at the
29	// same time (for example, AJAX requests triggered by the installer). If we
30	// didn't try to clear it whenever this function is called, the data in the
31	// cache would become stale; for example, the installer sometimes calls
32	// variable_set(), which updates the {variable} table and then clears the
33	// cache to make sure that the next page request picks up the new value.
34	// Not actually clearing the cache here therefore leads old variables to be
35	// loaded on the first page requests after installation, which can cause
36	// subtle bugs, some of which would not be fixed unless the site
37	// administrator cleared the cache manually.
38	try {
39	if (function_exists('drupal_install_initialize_database')) {
40	drupal_install_initialize_database();
41	parent::clear($cid, $wildcard);
42	}
43	}
44	// If the attempt at clearing the cache causes an error, that means that
45	// either the database connection is not set up yet or the relevant cache
46	// table in the database has not yet been created, so we can safely do
47	// nothing here.
48	catch (Exception $e) {
49	}
50	}
51
52	function isEmpty() {
53	return TRUE;
54	}
55	}