1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
|
<?php
/**
* @author Robin Appelman <icewind@owncloud.com>
*
* @copyright Copyright (c) 2016, ownCloud, Inc.
* @license AGPL-3.0
*
* This code is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License, version 3,
* along with this program. If not, see <http://www.gnu.org/licenses/>
*
*/
namespace OC\Cache;
use OCP\ICache;
/**
* In-memory cache with a capacity limit to keep memory usage in check
*
* Uses a simple FIFO expiry mechanism
*/
class CappedMemoryCache implements ICache, \ArrayAccess {
private $capacity;
private $cache = [];
public function __construct($capacity = 512) {
$this->capacity = $capacity;
}
public function hasKey($key) {
return isset($this->cache[$key]);
}
public function get($key) {
return isset($this->cache[$key]) ? $this->cache[$key] : null;
}
public function set($key, $value, $ttl = 0) {
$this->cache[$key] = $value;
$this->garbageCollect();
}
public function remove($key) {
unset($this->cache[$key]);
return true;
}
public function clear($prefix = '') {
$this->cache = [];
return true;
}
public function offsetExists($offset) {
return $this->hasKey($offset);
}
public function &offsetGet($offset) {
return $this->cache[$offset];
}
public function offsetSet($offset, $value) {
$this->set($offset, $value);
}
public function offsetUnset($offset) {
$this->remove($offset);
}
private function garbageCollect() {
while (count($this->cache) > $this->capacity) {
reset($this->cache);
$key = key($this->cache);
$this->remove($key);
}
}
}
|
