1: <?php
 2: /**
 3:  * Wei Framework
 4:  *
 5:  * @copyright   Copyright (c) 2008-2015 Twin Huang
 6:  * @license     http://opensource.org/licenses/mit-license.php MIT License
 7:  */
 8: 
 9: namespace Wei;
10: 
11: /**
12:  * A service that provide the functionality of exclusive Lock
13:  *
14:  * @author      Twin Huang <twinhuang@qq.com>
15:  * @property    Cache $cache A cache service
16:  */
17: class Lock extends Base
18: {
19:     /**
20:      * @var array
21:      */
22:     protected $keys = array();
23: 
24:     /**
25:      * Constructor
26:      *
27:      * @param array $options
28:      */
29:     public function __construct(array $options = array())
30:     {
31:         parent::__construct($options);
32: 
33:         register_shutdown_function(array($this, 'releaseAll'));
34: 
35:         // Release locks and exist when catch signal in CLI
36:         if (function_exists('pcntl_signal')) {
37:             pcntl_signal(SIGINT, array($this, 'catchSignal'));
38:             pcntl_signal(SIGTERM, array($this, 'catchSignal'));
39:         }
40:     }
41: 
42:     /**
43:      * Acquire a lock key
44:      *
45:      * @param string $key
46:      * @return bool
47:      */
48:     public function __invoke($key)
49:     {
50:         if ($this->cache->add($key, true)) {
51:             $this->keys[] = $key;
52:             return true;
53:         } else {
54:             return false;
55:         }
56:     }
57: 
58:     /**
59:      * Release a lock key
60:      *
61:      * @param string $key
62:      * @return bool
63:      */
64:     public function release($key)
65:     {
66:         if ($this->cache->remove($key)) {
67:             if (($index = array_search($key, $this->keys)) !== false) {
68:                 unset($this->keys[$index]);
69:             }
70:             return true;
71:         } else {
72:             return false;
73:         }
74:     }
75: 
76:     /**
77:      * Release all lock keys
78:      */
79:     public function releaseAll()
80:     {
81:         foreach ($this->keys as $key) {
82:             $this->release($key);
83:         }
84:     }
85: 
86:     /**
87:      * Release all lock keys and exit
88:      */
89:     public function catchSignal()
90:     {
91:         $this->releaseAll();
92:         exit;
93:     }
94: }