vendor/zendframework/zend-cache/src/Storage/Adapter/DbaIterator.php

   1 <?php
   2 /**
   3  * Zend Framework (http://framework.zend.com/)
   4  *
   5  * @link      http://github.com/zendframework/zf2 for the canonical source repository
   6  * @copyright Copyright (c) 2005-2016 Zend Technologies USA Inc. (http://www.zend.com)
   7  * @license   http://framework.zend.com/license/new-bsd New BSD License
   8  */
   9
  10 namespace Zend\Cache\Storage\Adapter;
  11
  12 use Zend\Cache\Exception;
  13 use Zend\Cache\Storage\IteratorInterface;
  14
  15 class DbaIterator implements IteratorInterface
  16 {
  17     /**
  18      * The apc storage instance
  19      *
  20      * @var Dba
  21      */
  22     protected $storage;
  23
  24     /**
  25      * The iterator mode
  26      *
  27      * @var int
  28      */
  29     protected $mode = IteratorInterface::CURRENT_AS_KEY;
  30
  31     /**
  32      * The dba resource handle
  33      *
  34      * @var resource
  35      */
  36     protected $handle;
  37
  38     /**
  39      * The length of the namespace prefix
  40      *
  41      * @var int
  42      */
  43     protected $prefixLength;
  44
  45     /**
  46      * The current internal key
  47      *
  48      * @var string|bool
  49      */
  50     protected $currentInternalKey;
  51
  52     /**
  53      * Constructor
  54      *
  55      * @param Dba      $storage
  56      * @param resource $handle
  57      * @param string   $prefix
  58      */
  59     public function __construct(Dba $storage, $handle, $prefix)
  60     {
  61         $this->storage      = $storage;
  62         $this->handle       = $handle;
  63         $this->prefixLength = strlen($prefix);
  64
  65         $this->rewind();
  66     }
  67
  68     /**
  69      * Get storage instance
  70      *
  71      * @return Dba
  72      */
  73     public function getStorage()
  74     {
  75         return $this->storage;
  76     }
  77
  78     /**
  79      * Get iterator mode
  80      *
  81      * @return int Value of IteratorInterface::CURRENT_AS_*
  82      */
  83     public function getMode()
  84     {
  85         return $this->mode;
  86     }
  87
  88     /**
  89      * Set iterator mode
  90      *
  91      * @param int $mode
  92      * @return DbaIterator Provides a fluent interface
  93      */
  94     public function setMode($mode)
  95     {
  96         $this->mode = (int) $mode;
  97         return $this;
  98     }
  99
 100     /* Iterator */
 101
 102     /**
 103      * Get current key, value or metadata.
 104      *
 105      * @return mixed
 106      * @throws Exception\RuntimeException
 107      */
 108     public function current()
 109     {
 110         if ($this->mode == IteratorInterface::CURRENT_AS_SELF) {
 111             return $this;
 112         }
 113
 114         $key = $this->key();
 115
 116         if ($this->mode == IteratorInterface::CURRENT_AS_VALUE) {
 117             return $this->storage->getItem($key);
 118         } elseif ($this->mode == IteratorInterface::CURRENT_AS_METADATA) {
 119             return $this->storage->getMetadata($key);
 120         }
 121
 122         return $key;
 123     }
 124
 125     /**
 126      * Get current key
 127      *
 128      * @return string
 129      * @throws Exception\RuntimeException
 130      */
 131     public function key()
 132     {
 133         if ($this->currentInternalKey === false) {
 134             throw new Exception\RuntimeException("Iterator is on an invalid state");
 135         }
 136
 137         // remove namespace prefix
 138         return substr($this->currentInternalKey, $this->prefixLength);
 139     }
 140
 141     /**
 142      * Move forward to next element
 143      *
 144      * @return void
 145      * @throws Exception\RuntimeException
 146      */
 147     public function next()
 148     {
 149         if ($this->currentInternalKey === false) {
 150             throw new Exception\RuntimeException("Iterator is on an invalid state");
 151         }
 152
 153         $this->currentInternalKey = dba_nextkey($this->handle);
 154
 155         // Workaround for PHP-Bug #62492
 156         if ($this->currentInternalKey === null) {
 157             $this->currentInternalKey = false;
 158         }
 159     }
 160
 161     /**
 162      * Checks if current position is valid
 163      *
 164      * @return bool
 165      */
 166     public function valid()
 167     {
 168         return ($this->currentInternalKey !== false);
 169     }
 170
 171     /**
 172      * Rewind the Iterator to the first element.
 173      *
 174      * @return void
 175      * @throws Exception\RuntimeException
 176      */
 177     public function rewind()
 178     {
 179         if ($this->currentInternalKey === false) {
 180             throw new Exception\RuntimeException("Iterator is on an invalid state");
 181         }
 182
 183         $this->currentInternalKey = dba_firstkey($this->handle);
 184
 185         // Workaround for PHP-Bug #62492
 186         if ($this->currentInternalKey === null) {
 187             $this->currentInternalKey = false;
 188         }
 189     }
 190 }