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 int $inputType 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                         if ( !class_exists( 'MemcachedClientforWiki' ) ) {
  56                                 class MemCachedClientforWiki extends memcached {
  57                                         function _debugprint( $text ) {
  58                                                 wfDebug( "memcached: $text" );
  59                                         }
  60                                 }
  61                         }
  62                         $wgCaches[CACHE_MEMCACHED] = new MemCachedClientforWiki(
  63                                 array('persistant' => $wgMemCachedPersistent, 'compress_threshold' => 1500 ) );
  64                         $wgCaches[CACHE_MEMCACHED]->set_servers( $wgMemCachedServers );
  65                         $wgCaches[CACHE_MEMCACHED]->set_debug( $wgMemCachedDebug );
  66                 }
  67                 $cache =& $wgCaches[CACHE_MEMCACHED];
  68         } elseif ( $type == CACHE_ACCEL ) {
  69                 if ( !array_key_exists( CACHE_ACCEL, $wgCaches ) ) {
  70                         if ( function_exists( 'eaccelerator_get' ) ) {
  71                                 $wgCaches[CACHE_ACCEL] = new eAccelBagOStuff;
  72                         } elseif ( function_exists( 'apc_fetch') ) {
  73                                 $wgCaches[CACHE_ACCEL] = new APCBagOStuff;
  74                         } elseif( function_exists( 'xcache_get' ) ) {
  75                                 $wgCaches[CACHE_ACCEL] = new XCacheBagOStuff();
  76                         } elseif ( function_exists( 'mmcache_get' ) ) {
  77                                 $wgCaches[CACHE_ACCEL] = new TurckBagOStuff;
  78                         } else {
  79                                 $wgCaches[CACHE_ACCEL] = false;
  80                         }
  81                 }
  82                 if ( $wgCaches[CACHE_ACCEL] !== false ) {
  83                         $cache =& $wgCaches[CACHE_ACCEL];
  84                 }
  85         } elseif ( $type == CACHE_DBA ) {
  86                 if ( !array_key_exists( CACHE_DBA, $wgCaches ) ) {
  87                         $wgCaches[CACHE_DBA] = new DBABagOStuff;
  88                 }
  89                 $cache =& $wgCaches[CACHE_DBA];
  90         }
  91
  92         if ( $type == CACHE_DB || ( $inputType == CACHE_ANYTHING && $cache === false ) ) {
  93                 if ( !array_key_exists( CACHE_DB, $wgCaches ) ) {
  94                         $wgCaches[CACHE_DB] = new MediaWikiBagOStuff('objectcache');
  95                 }
  96                 $cache =& $wgCaches[CACHE_DB];
  97         }
  98
  99         if ( $cache === false ) {
 100                 if ( !array_key_exists( CACHE_NONE, $wgCaches ) ) {
 101                         $wgCaches[CACHE_NONE] = new FakeMemCachedClient;
 102                 }
 103                 $cache =& $wgCaches[CACHE_NONE];
 104         }
 105
 106         return $cache;
 107 }
 108
 109 /** Get the main cache object */
 110 function &wfGetMainCache() {
 111         global $wgMainCacheType;
 112         $ret =& wfGetCache( $wgMainCacheType );
 113         return $ret;
 114 }
 115
 116 /** Get the cache object used by the message cache */
 117 function &wfGetMessageCacheStorage() {
 118         global $wgMessageCacheType;
 119         $ret =& wfGetCache( $wgMessageCacheType );
 120         return $ret;
 121 }
 122
 123 /** Get the cache object used by the parser cache */
 124 function &wfGetParserCacheStorage() {
 125         global $wgParserCacheType;
 126         $ret =& wfGetCache( $wgParserCacheType );
 127         return $ret;
 128 }