diff options
Diffstat (limited to 'includes/cache.inc')
| -rw-r--r-- | includes/cache.inc | 75 |
1 files changed, 60 insertions, 15 deletions
diff --git a/includes/cache.inc b/includes/cache.inc index 1559d3429..3b0b149ff 100644 --- a/includes/cache.inc +++ b/includes/cache.inc @@ -6,19 +6,22 @@ * * @param $key * The cache ID of the data to retrieve. + * @param $table + * The table $table to store the data in. Valid core values are 'cache_filter', + * 'cache_menu', 'cache_page', or 'cache' for the default cache. */ -function cache_get($key) { +function cache_get($key, $table = 'cache') { global $user; // Garbage collection necessary when enforcing a minimum cache lifetime $cache_flush = variable_get('cache_flush', 0); if ($cache_flush && ($cache_flush + variable_get('cache_lifetime', 0) <= time())) { // Time to flush old cache data - db_query("DELETE FROM {cache} WHERE expire != %d AND expire <= %d", CACHE_PERMANENT, $cache_flush); + db_query("DELETE FROM {%s} WHERE expire != %d AND expire <= %d", $table, CACHE_PERMANENT, $cache_flush); variable_set('cache_flush', 0); } - $cache = db_fetch_object(db_query("SELECT data, created, headers, expire FROM {cache} WHERE cid = '%s'", $key)); + $cache = db_fetch_object(db_query("SELECT data, created, headers, expire FROM {%s} WHERE cid = '%s'", $table, $key)); if (isset($cache->data)) { // If the data is permanent or we're not enforcing a minimum cache lifetime // always return the cached data. @@ -47,8 +50,33 @@ function cache_get($key) { /** * Store data in the persistent cache. * + * The persistent cache is split up into four database + * tables. Contributed modules can add additional tables. + * + * 'cache_page': This table stores generated pages for anonymous + * users. This is the only table affected by the page cache setting on + * the administrator panel. + * + * 'cache_menu': Stores the cachable part of the users' menus. + * + * 'cache_filter': Stores filtered pieces of content. This table is + * periodically cleared of stale entries by cron. + * + * 'cache': Generic cache storage table. + * + * The reasons for having several tables are as follows: + * + * - smaller tables allow for faster selects and inserts + * - we try to put fast changing cache items and rather static + * ones into different tables. The effect is that only the fast + * changing tables will need a lot of writes to disk. The more + * static tables will also be better cachable with MySQL's query cache + * * @param $cid * The cache ID of the data to store. + * @param $table + * The table $table to store the data in. Valid core values are 'cache_filter', + * 'cache_menu', 'cache_page', or 'cache'. * @param $data * The data to store in the cache. Complex data types must be serialized first. * @param $expire @@ -62,29 +90,41 @@ function cache_get($key) { * @param $headers * A string containing HTTP header information for cached pages. */ -function cache_set($cid, $data, $expire = CACHE_PERMANENT, $headers = NULL) { - db_lock_table('cache'); - db_query("UPDATE {cache} SET data = %b, created = %d, expire = %d, headers = '%s' WHERE cid = '%s'", $data, time(), $expire, $headers, $cid); +function cache_set($cid, $table = 'cache', $data, $expire = CACHE_PERMANENT, $headers = NULL) { + db_lock_table($table); + db_query("UPDATE {%s} SET data = '%s', created = %d, expire = %d, headers = '%s' WHERE cid = '%s'", $table, $data, time(), $expire, $headers, $cid); if (!db_affected_rows()) { - @db_query("INSERT INTO {cache} (cid, data, created, expire, headers) VALUES ('%s', %b, %d, %d, '%s')", $cid, $data, time(), $expire, $headers); + @db_query("INSERT INTO {%s} (cid, data, created, expire, headers) VALUES ('%s', '%s', %d, %d, '%s')", $table, $cid, $data, time(), $expire, $headers); } db_unlock_tables(); } /** - * Expire data from the cache. + * + * Expire data from the cache. If called without arguments, expirable + * entries will be cleared from the cache_page table. * * @param $cid * If set, the cache ID to delete. Otherwise, all cache entries that can * expire are deleted. * + * @param $table + * If set, the table $table to delete from. Mandatory + * argument if $cid is set. + * * @param $wildcard - * If set to TRUE, the $cid is treated as a substring to match rather than a - * complete ID. + * 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 $table will be emptied. */ -function cache_clear_all($cid = NULL, $wildcard = FALSE) { +function cache_clear_all($cid = NULL, $table = NULL, $wildcard = FALSE) { global $user; + if (!isset($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 $user->cache variable which @@ -101,21 +141,26 @@ function cache_clear_all($cid = NULL, $wildcard = FALSE) { else if (time() > ($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 {cache} WHERE expire != %d AND expire < %d", CACHE_PERMANENT, time()); + 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 {cache} WHERE expire != %d AND expire < %d", CACHE_PERMANENT, time()); + db_query("DELETE FROM {%s} WHERE expire != %d AND expire < %d", $table, CACHE_PERMANENT, time()); } } else { if ($wildcard) { - db_query("DELETE FROM {cache} WHERE cid LIKE '%%%s%%'", $cid); + if ($cid == '*') { + db_query("TRUNCATE TABLE {%s}", $table); + } + else { + db_query("DELETE FROM {%s} WHERE cid LIKE '%s%%'", $table, $cid); + } } else { - db_query("DELETE FROM {cache} WHERE cid = '%s'", $cid); + db_query("DELETE FROM {%s} WHERE cid = '%s'", $table, $cid); } } } |