|
1
|
|
|
<?php |
|
2
|
|
|
/** |
|
3
|
|
|
* @link http://www.yiiframework.com/ |
|
4
|
|
|
* @copyright Copyright (c) 2008 Yii Software LLC |
|
5
|
|
|
* @license http://www.yiiframework.com/license/ |
|
6
|
|
|
*/ |
|
7
|
|
|
|
|
8
|
|
|
namespace yii\mutex; |
|
9
|
|
|
|
|
10
|
|
|
use yii\base\Component; |
|
11
|
|
|
|
|
12
|
|
|
/** |
|
13
|
|
|
* The Mutex component allows mutual execution of concurrent processes in order to prevent "race conditions". |
|
14
|
|
|
* |
|
15
|
|
|
* This is achieved by using a "lock" mechanism. Each possibly concurrent thread cooperates by acquiring |
|
16
|
|
|
* a lock before accessing the corresponding data. |
|
17
|
|
|
* |
|
18
|
|
|
* Usage examples: |
|
19
|
|
|
* |
|
20
|
|
|
* ``` |
|
21
|
|
|
* if ($mutex->acquire($mutexName)) { |
|
22
|
|
|
* // business logic execution |
|
23
|
|
|
* } else { |
|
24
|
|
|
* // execution is blocked! |
|
25
|
|
|
* } |
|
26
|
|
|
* ``` |
|
27
|
|
|
* |
|
28
|
|
|
* ``` |
|
29
|
|
|
* $mutex->sync($mutexName, 10, function () { |
|
30
|
|
|
* // business logic execution with synchronization |
|
31
|
|
|
* })); |
|
32
|
|
|
* ``` |
|
33
|
|
|
* |
|
34
|
|
|
* This is a base class, which should be extended in order to implement the actual lock mechanism. |
|
35
|
|
|
* |
|
36
|
|
|
* @author resurtm <[email protected]> |
|
37
|
|
|
* @since 2.0 |
|
38
|
|
|
*/ |
|
39
|
|
|
abstract class Mutex extends Component |
|
40
|
|
|
{ |
|
41
|
|
|
/** |
|
42
|
|
|
* @var bool whether all locks acquired in this process (i.e. local locks) must be released automatically |
|
43
|
|
|
* before finishing script execution. Defaults to true. Setting this property to true means that all locks |
|
44
|
|
|
* acquired in this process must be released (regardless of errors or exceptions). |
|
45
|
|
|
*/ |
|
46
|
|
|
public $autoRelease = true; |
|
47
|
|
|
|
|
48
|
|
|
/** |
|
49
|
|
|
* @var string[] names of the locks acquired by the current PHP process. |
|
50
|
|
|
*/ |
|
51
|
|
|
private $_locks = []; |
|
52
|
|
|
|
|
53
|
|
|
|
|
54
|
|
|
/** |
|
55
|
|
|
* Initializes the Mutex component. |
|
56
|
|
|
*/ |
|
57
|
16 |
|
public function init() |
|
58
|
|
|
{ |
|
59
|
16 |
|
if ($this->autoRelease) { |
|
60
|
16 |
|
$locks = &$this->_locks; |
|
61
|
16 |
|
register_shutdown_function(function () use (&$locks) { |
|
62
|
|
|
foreach ($locks as $lock) { |
|
63
|
|
|
$this->release($lock); |
|
64
|
|
|
} |
|
65
|
16 |
|
}); |
|
66
|
|
|
} |
|
67
|
16 |
|
} |
|
68
|
|
|
|
|
69
|
|
|
/** |
|
70
|
|
|
* Acquires a lock by name. |
|
71
|
|
|
* @param string $name of the lock to be acquired. Must be unique. |
|
72
|
|
|
* @param int $timeout time (in seconds) to wait for lock to be released. Defaults to zero meaning that method will return |
|
73
|
|
|
* false immediately in case lock was already acquired. |
|
74
|
|
|
* @return bool lock acquiring result. |
|
75
|
|
|
*/ |
|
76
|
16 |
|
public function acquire($name, $timeout = 0) |
|
77
|
|
|
{ |
|
78
|
16 |
|
if ($this->acquireLock($name, $timeout)) { |
|
79
|
16 |
|
$this->_locks[] = $name; |
|
80
|
|
|
|
|
81
|
16 |
|
return true; |
|
82
|
|
|
} |
|
83
|
|
|
|
|
84
|
9 |
|
return false; |
|
85
|
|
|
} |
|
86
|
|
|
|
|
87
|
|
|
/** |
|
88
|
|
|
* Releases acquired lock. This method will return false in case the lock was not found. |
|
89
|
|
|
* @param string $name of the lock to be released. This lock must already exist. |
|
90
|
|
|
* @return bool lock release result: false in case named lock was not found.. |
|
91
|
|
|
*/ |
|
92
|
13 |
|
public function release($name) |
|
93
|
|
|
{ |
|
94
|
13 |
|
if ($this->releaseLock($name)) { |
|
95
|
13 |
|
$index = array_search($name, $this->_locks); |
|
96
|
13 |
|
if ($index !== false) { |
|
97
|
13 |
|
unset($this->_locks[$index]); |
|
98
|
|
|
} |
|
99
|
|
|
|
|
100
|
13 |
|
return true; |
|
101
|
|
|
} |
|
102
|
|
|
|
|
103
|
|
|
return false; |
|
104
|
|
|
} |
|
105
|
|
|
|
|
106
|
|
|
/** |
|
107
|
|
|
* Executes callback with mutex synchronization. |
|
108
|
|
|
* |
|
109
|
|
|
* @param string $name of the lock to be acquired. Must be unique. |
|
110
|
|
|
* @param int $timeout time (in seconds) to wait for lock to be released. |
|
111
|
|
|
* @param callable $callback a valid PHP callback that performs the job. Accepts mutex instance as parameter. |
|
112
|
|
|
* @param bool $throw whether to throw an exception when the lock is not acquired. |
|
113
|
|
|
* @return mixed result of callback function, or null when the lock is not acquired. |
|
114
|
|
|
* @throws SyncException when the lock is not acquired. |
|
115
|
|
|
* @since 2.1 |
|
116
|
|
|
*/ |
|
117
|
9 |
|
public function sync($name, $timeout, callable $callback, $throw = true) |
|
118
|
|
|
{ |
|
119
|
9 |
|
if ($this->acquire($name, $timeout)) { |
|
120
|
|
|
try { |
|
121
|
3 |
|
$result = call_user_func($callback, $this); |
|
122
|
3 |
|
} finally { |
|
123
|
3 |
|
$this->release($name); |
|
124
|
|
|
} |
|
125
|
3 |
|
return $result; |
|
126
|
|
|
} |
|
127
|
6 |
|
if ($throw) { |
|
128
|
3 |
|
throw new SyncException('Cannot acquire the lock.'); |
|
129
|
|
|
} |
|
130
|
3 |
|
return null; |
|
131
|
|
|
} |
|
132
|
|
|
|
|
133
|
|
|
/** |
|
134
|
|
|
* This method should be extended by a concrete Mutex implementations. Acquires lock by name. |
|
135
|
|
|
* @param string $name of the lock to be acquired. |
|
136
|
|
|
* @param int $timeout time (in seconds) to wait for the lock to be released. |
|
137
|
|
|
* @return bool acquiring result. |
|
138
|
|
|
*/ |
|
139
|
|
|
abstract protected function acquireLock($name, $timeout = 0); |
|
140
|
|
|
|
|
141
|
|
|
/** |
|
142
|
|
|
* This method should be extended by a concrete Mutex implementations. Releases lock by given name. |
|
143
|
|
|
* @param string $name of the lock to be released. |
|
144
|
|
|
* @return bool release result. |
|
145
|
|
|
*/ |
|
146
|
|
|
abstract protected function releaseLock($name); |
|
147
|
|
|
} |
|
148
|
|
|
|
yiisoft /
yii2
