includes/ObjectCache.php

   1 <?php
   2 /**
   3  * @file
   4  * @ingroup Cache
   5  */
   6
   7 /**
   8  * FakeMemCachedClient imitates the API of memcached-client v. 0.1.2.
   9  * It acts as a memcached server with no RAM, that is, all objects are
  10  * cleared the moment they are set. All set operations succeed and all
  11  * get operations return null.
  12  * @ingroup Cache
  13  */
  14 class FakeMemCachedClient {
  15         function add ($key, $val, $exp = 0) { return true; }
  16         function decr ($key, $amt=1) { return null; }
  17         function delete ($key, $time = 0) { return false; }
  18         function disconnect_all () { }
  19         function enable_compress ($enable) { }
  20         function forget_dead_hosts () { }
  21         function get ($key) { return null; }
  22         function get_multi ($keys) { return array_pad(array(), count($keys), null); }
  23         function incr ($key, $amt=1) { return null; }
  24         function replace ($key, $value, $exp=0) { return false; }
  25         function run_command ($sock, $cmd) { return null; }
  26         function set ($key, $value, $exp=0){ return true; }
  27         function set_compress_threshold ($thresh){ }
  28         function set_debug ($dbg) { }
  29         function set_servers ($list) { }
  30 }
  31
  32 global $wgCaches;
  33 $wgCaches = array();
  34
  35 /**
  36  * Get a cache object.
  37  * @param $inputType Integer: cache type, one the the CACHE_* constants.
  38  */
  39 function &wfGetCache( $inputType ) {
  40         global $wgCaches, $wgMemCachedServers, $wgMemCachedDebug, $wgMemCachedPersistent;
  41         $cache = false;
  42
  43         if ( $inputType == CACHE_ANYTHING ) {
  44                 reset( $wgCaches );
  45                 $type = key( $wgCaches );
  46                 if ( $type === false || $type === CACHE_NONE ) {
  47                         $type = CACHE_DB;
  48                 }
  49         } else {
  50                 $type = $inputType;
  51         }
  52
  53         if ( $type == CACHE_MEMCACHED ) {
  54                 if ( !array_key_exists( CACHE_MEMCACHED, $wgCaches ) ) {
  55                         $wgCaches[CACHE_MEMCACHED] = new MemCachedClientforWiki(
  56                                 array('persistant' => $wgMemCachedPersistent, 'compress_threshold' => 1500 ) );
  57                         $wgCaches[CACHE_MEMCACHED]->set_servers( $wgMemCachedServers );
  58                         $wgCaches[CACHE_MEMCACHED]->set_debug( $wgMemCachedDebug );
  59                 }
  60                 $cache =& $wgCaches[CACHE_MEMCACHED];
  61         } elseif ( $type == CACHE_ACCEL ) {
  62                 if ( !array_key_exists( CACHE_ACCEL, $wgCaches ) ) {
  63                         if ( function_exists( 'eaccelerator_get' ) ) {
  64                                 $wgCaches[CACHE_ACCEL] = new eAccelBagOStuff;
  65                         } elseif ( function_exists( 'apc_fetch') ) {
  66                                 $wgCaches[CACHE_ACCEL] = new APCBagOStuff;
  67                         } elseif( function_exists( 'xcache_get' ) ) {
  68                                 $wgCaches[CACHE_ACCEL] = new XCacheBagOStuff();
  69                         } else {
  70                                 $wgCaches[CACHE_ACCEL] = false;
  71                         }
  72                 }
  73                 if ( $wgCaches[CACHE_ACCEL] !== false ) {
  74                         $cache =& $wgCaches[CACHE_ACCEL];
  75                 }
  76         } elseif ( $type == CACHE_DBA ) {
  77                 if ( !array_key_exists( CACHE_DBA, $wgCaches ) ) {
  78                         $wgCaches[CACHE_DBA] = new DBABagOStuff;
  79                 }
  80                 $cache =& $wgCaches[CACHE_DBA];
  81         }
  82
  83         if ( $type == CACHE_DB || ( $inputType == CACHE_ANYTHING && $cache === false ) ) {
  84                 if ( !array_key_exists( CACHE_DB, $wgCaches ) ) {
  85                         $wgCaches[CACHE_DB] = new SqlBagOStuff('objectcache');
  86                 }
  87                 $cache =& $wgCaches[CACHE_DB];
  88         }
  89
  90         if ( $cache === false ) {
  91                 if ( !array_key_exists( CACHE_NONE, $wgCaches ) ) {
  92                         $wgCaches[CACHE_NONE] = new FakeMemCachedClient;
  93                 }
  94                 $cache =& $wgCaches[CACHE_NONE];
  95         }
  96
  97         return $cache;
  98 }
  99
 100 /** Get the main cache object */
 101 function &wfGetMainCache() {
 102         global $wgMainCacheType;
 103         $ret =& wfGetCache( $wgMainCacheType );
 104         return $ret;
 105 }
 106
 107 /** Get the cache object used by the message cache */
 108 function &wfGetMessageCacheStorage() {
 109         global $wgMessageCacheType;
 110         $ret =& wfGetCache( $wgMessageCacheType );
 111         return $ret;
 112 }
 113
 114 /** Get the cache object used by the parser cache */
 115 function &wfGetParserCacheStorage() {
 116         global $wgParserCacheType;
 117         $ret =& wfGetCache( $wgParserCacheType );
 118         return $ret;
 119 }