3 * Object caching using PHP's APC accelerator.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 * http://www.gnu.org/copyleft/gpl.html
25 * This is a wrapper for APC's shared memory functions
29 class APCBagOStuff
extends BagOStuff
{
32 * @var bool If true, trust the APC implementation to serialize and
33 * deserialize objects correctly. If false, (de-)serialize in PHP.
35 protected $nativeSerialize;
38 * @var string String to append to each APC key. This may be changed
39 * whenever the handling of values is changed, to prevent existing code
40 * from encountering older values which it cannot handle.
42 const KEY_SUFFIX
= ':2';
45 * Available parameters are:
46 * - nativeSerialize: If true, pass objects to apc_store(), and trust it
47 * to serialize them correctly. If false, serialize
50 * @param array $params
52 public function __construct( array $params = [] ) {
53 parent
::__construct( $params );
55 if ( isset( $params['nativeSerialize'] ) ) {
56 $this->nativeSerialize
= $params['nativeSerialize'];
57 } elseif ( extension_loaded( 'apcu' ) && ini_get( 'apc.serializer' ) === 'default' ) {
58 // APCu has a memory corruption bug when the serializer is set to 'default'.
59 // See T120267, and upstream bug reports:
60 // - https://github.com/krakjoe/apcu/issues/38
61 // - https://github.com/krakjoe/apcu/issues/35
62 // - https://github.com/krakjoe/apcu/issues/111
63 $this->logger
->warning(
64 'The APCu extension is loaded and the apc.serializer INI setting ' .
65 'is set to "default". This can cause memory corruption! ' .
66 'You should change apc.serializer to "php" instead. ' .
67 'See <https://github.com/krakjoe/apcu/issues/38>.'
69 $this->nativeSerialize
= false;
71 $this->nativeSerialize
= true;
75 protected function doGet( $key, $flags = 0 ) {
76 return $this->unserialize( apc_fetch( $key . self
::KEY_SUFFIX
) );
79 protected function getWithToken( $key, &$casToken, $flags = 0 ) {
82 $blob = apc_fetch( $key . self
::KEY_SUFFIX
);
83 $value = $this->unserialize( $blob );
84 if ( $value !== false ) {
85 $casToken = $blob; // don't bother hashing this
91 public function set( $key, $value, $exptime = 0, $flags = 0 ) {
93 $key . self
::KEY_SUFFIX
,
94 $this->serialize( $value ),
101 public function add( $key, $value, $exptime = 0, $flags = 0 ) {
103 $key . self
::KEY_SUFFIX
,
104 $this->serialize( $value ),
109 public function delete( $key, $flags = 0 ) {
110 apc_delete( $key . self
::KEY_SUFFIX
);
115 public function incr( $key, $value = 1 ) {
116 return apc_inc( $key . self
::KEY_SUFFIX
, $value );
119 public function decr( $key, $value = 1 ) {
120 return apc_dec( $key . self
::KEY_SUFFIX
, $value );
123 public function merge( $key, callable
$callback, $exptime = 0, $attempts = 10, $flags = 0 ) {
124 return $this->mergeViaCas( $key, $callback, $exptime, $attempts, $flags );
127 protected function serialize( $value ) {
128 if ( !$this->nativeSerialize
&& !$this->isInteger( $value ) ) {
129 $value = serialize( $value );
134 protected function unserialize( $value ) {
135 if ( is_string( $value ) && !$this->nativeSerialize
) {
136 $value = $this->isInteger( $value )
138 : unserialize( $value );