| 1 |  |  | <?php | 
            
                                                                                                            
                            
            
                                    
            
            
                | 2 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 3 |  |  | /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 4 |  |  |  * This file is part of the PHP Generics package. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 5 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 6 |  |  |  * @package Generics | 
            
                                                                                                            
                            
            
                                    
            
            
                | 7 |  |  |  */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 8 |  |  | namespace Generics\Streams; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 9 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 10 |  |  | use \Generics\FileNotFoundException; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 11 |  |  | use \Generics\Resettable; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 12 |  |  | use \Generics\Lockable; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 13 |  |  | use \Generics\LockException; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 14 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 15 |  |  | /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 16 |  |  |  * This class provides an input stream for files. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 17 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 18 |  |  |  * @author Maik Greubel <[email protected]> | 
            
                                                                                                            
                            
            
                                    
            
            
                | 19 |  |  |  */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 20 |  |  | class FileInputStream implements InputStream, Resettable, Lockable | 
            
                                                                                                            
                            
            
                                    
            
            
                | 21 |  |  | { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 22 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 23 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 24 |  |  |      * The file handle | 
            
                                                                                                            
                            
            
                                    
            
            
                | 25 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 26 |  |  |      * @var resource | 
            
                                                                                                            
                            
            
                                    
            
            
                | 27 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 28 |  |  |     private $handle; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 29 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 30 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 31 |  |  |      * The absolute file path and name | 
            
                                                                                                            
                            
            
                                    
            
            
                | 32 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 33 |  |  |      * @var string | 
            
                                                                                                            
                            
            
                                    
            
            
                | 34 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 35 |  |  |     private $fileName; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 36 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 37 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 38 |  |  |      * Whether the access is locked | 
            
                                                                                                            
                            
            
                                    
            
            
                | 39 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 40 |  |  |      * @var boolean | 
            
                                                                                                            
                            
            
                                    
            
            
                | 41 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 42 |  |  |     private $locked; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 43 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 44 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 45 |  |  |      * Create a new FileInputStream | 
            
                                                                                                            
                            
            
                                    
            
            
                | 46 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 47 |  |  |      * @param string $file | 
            
                                                                                                            
                            
            
                                    
            
            
                | 48 |  |  |      *            The absolute (or relative) path to the file to open | 
            
                                                                                                            
                            
            
                                    
            
            
                | 49 |  |  |      * @throws FileNotFoundException | 
            
                                                                                                            
                            
            
                                    
            
            
                | 50 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 51 | 23 |  |     public function __construct($file) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 52 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 53 | 23 |  |         if (! file_exists($file)) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 54 | 1 |  |             throw new FileNotFoundException("File {file} could not be found", array( | 
            
                                                                                                            
                            
            
                                    
            
            
                | 55 |  |  |                 'file' => $file | 
            
                                                                                                            
                            
            
                                    
            
            
                | 56 | 1 |  |             )); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 57 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 58 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 59 | 22 |  |         $this->handle = fopen($file, "rb"); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 60 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 61 | 22 |  |         if (! $this->ready()) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 62 |  |  |             throw new StreamException("Could not open {file} for reading", array( | 
            
                                                                                                            
                            
            
                                    
            
            
                | 63 |  |  |                 'file' => $file | 
            
                                                                                                            
                            
            
                                    
            
            
                | 64 |  |  |             )); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 65 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 66 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 67 | 22 |  |         $this->fileName = $file; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 68 | 22 |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 69 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 70 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 71 |  |  |      * Cleanup (e.g. release lock) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 72 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 73 | 22 |  |     public function __destruct() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 74 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 75 |  |  |         try { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 76 | 22 |  |             if ($this->locked) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 77 | 1 |  |                 $this->unlock(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 78 | 1 |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 79 | 22 |  |         } catch (\Generics\GenericsException $ex) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 80 |  |  |             // Do nothing | 
            
                                                                                                            
                            
            
                                    
            
            
                | 81 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 82 | 22 |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 83 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 84 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 85 |  |  |      * {@inheritDoc} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 86 |  |  |      * @see \Generics\Streams\Stream::close() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 87 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 88 |  |  |     public function close() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 89 | 16 |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 90 |  |  |         if ($this->handle != null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 91 | 16 |  |             fclose($this->handle); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 92 | 16 |  |             $this->handle = null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 93 | 16 |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 94 | 16 |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 95 | 16 |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 96 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 97 |  |  |      * {@inheritDoc} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 98 |  |  |      * @see \Generics\Streams\Stream::ready() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 99 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 100 |  |  |     public function ready() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 101 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 102 | 22 |  |         return is_resource($this->handle) && ! feof($this->handle); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 103 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 104 | 22 |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 105 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 106 |  |  |      * {@inheritDoc} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 107 |  |  |      * @see \Generics\Streams\InputStream::read() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 108 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 109 |  |  |     public function read($length = 1, $offset = null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 110 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 111 |  |  |         if (! $this->ready()) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 112 | 18 |  |             throw new StreamException("Stream is not ready!"); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 113 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 114 | 18 |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 115 | 1 |  |         if ($offset !== null && intval($offset) > 0) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 116 |  |  |             if (fseek($this->handle, $offset, SEEK_SET) != 0) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 117 |  |  |                 throw new StreamException("Could not set offset!"); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 118 | 17 |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 119 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 120 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 121 |  |  |         return fread($this->handle, $length); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 122 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 123 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 124 | 17 |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 125 |  |  |      * {@inheritDoc} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 126 |  |  |      * @see \Countable::count() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 127 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 128 |  |  |     public function count() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 129 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 130 |  |  |         $stat = fstat($this->handle); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 131 |  |  |         return $stat['size']; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 132 | 3 |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 133 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 134 | 3 |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 135 | 3 |  |      *{@inheritDoc} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 136 |  |  |      * @see \Generics\Streams\InputStream::reset() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 137 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 138 |  |  |     public function reset() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 139 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 140 |  |  |         fseek($this->handle, 0, SEEK_SET); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 141 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 142 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 143 | 2 |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 144 |  |  |      * {@inheritDoc} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 145 | 2 |  |      * @see \Generics\Lockable::lock() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 146 | 2 |  |      */ | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 147 |  | View Code Duplication |     public function lock() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 148 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 149 |  |  |         if ($this->locked || flock($this->handle, LOCK_SH) === false) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 150 |  |  |             throw new LockException("Could not acquire lock"); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 151 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 152 |  |  |         $this->locked = true; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 153 | 2 |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 154 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 155 | 2 |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 156 | 1 |  |      * {@inheritDoc} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 157 |  |  |      * @see \Generics\Lockable::unlock() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 158 | 2 |  |      */ | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 159 | 2 | View Code Duplication |     public function unlock() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 160 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 161 |  |  |         if (!$this->locked || flock($this->handle, LOCK_UN) === false) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 162 |  |  |             throw new LockException("Could not release lock"); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 163 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 164 |  |  |         $this->locked = false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 165 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 166 | 2 |  |      | 
            
                                                                                                            
                            
            
                                    
            
            
                | 167 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 168 | 2 |  |      * {@inheritDoc} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 169 |  |  |      * @see \Generics\Lockable::isLocked() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 170 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 171 | 2 |  |     public function isLocked() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 172 | 2 |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 173 |  |  |     	return $this->locked; | 
                            
                    |  |  |  | 
                                                                                        
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                | 174 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 175 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 176 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 177 |  |  |      * Retrieve the file path and name | 
            
                                                                                                            
                            
            
                                    
            
            
                | 178 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 179 |  |  |      * @return string | 
            
                                                                                                            
                            
            
                                    
            
            
                | 180 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 181 |  |  |     public function __toString() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 182 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 183 |  |  |         return realpath($this->fileName); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 184 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 185 |  |  |      | 
            
                                                                                                            
                            
            
                                    
            
            
                | 186 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 187 |  |  |      * {@inheritDoc} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 188 |  |  |      * @see \Generics\Streams\Stream::isOpen() | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 189 |  |  |      */ | 
            
                                                        
            
                                    
            
            
                | 190 |  |  |     public function isOpen() | 
            
                                                        
            
                                    
            
            
                | 191 |  |  |     { | 
            
                                                        
            
                                    
            
            
                | 192 |  |  |     	return is_resource($this->handle); | 
            
                                                        
            
                                    
            
            
                | 193 |  |  |     } | 
            
                                                        
            
                                    
            
            
                | 194 |  |  | } | 
            
                                                        
            
                                    
            
            
                | 195 |  |  |  | 
            
                        
If you return a value from a function or method, it should be a sub-type of the type that is given by the parent type f.e. an interface, or abstract method. This is more formally defined by the Lizkov substitution principle, and guarantees that classes that depend on the parent type can use any instance of a child type interchangably. This principle also belongs to the SOLID principles for object oriented design.
Let’s take a look at an example:
Our function
my_functionexpects aPostobject, and outputs the author of the post. The base classPostreturns a simple string and outputting a simple string will work just fine. However, the child classBlogPostwhich is a sub-type ofPostinstead decided to return anobject, and is therefore violating the SOLID principles. If aBlogPostwere passed tomy_function, PHP would not complain, but ultimately fail when executing thestrtouppercall in its body.