inc/classes/main/file_directories/input/raw/class_FrameworkRawFileInputPointer.php

   1 <?php
   2 /**
   3  * A class for reading files
   4  *
   5  * @author              Roland Haeder <webmaster@shipsimu.org>
   6  * @version             0.0.0
   7  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2014 Core Developer Team
   8  * @license             GNU GPL 3.0 or any newer version
   9  * @link                http://www.shipsimu.org
  10  *
  11  * This program is free software: you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation, either version 3 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  23  */
  24 class FrameworkRawFileInputPointer extends BaseFileIo implements InputPointer {
  25         /**
  26          * Protected constructor
  27          *
  28          * @return      void
  29          */
  30         protected function __construct () {
  31                 // Call parent constructor
  32                 parent::__construct(__CLASS__);
  33         }
  34
  35         /**
  36          * Create a file pointer based on the given file. The file will also
  37          * be verified here.
  38          *
  39          * @param       $fileName       The file name we shall pass to fopen()
  40          * @throws      FileIsEmptyException    If the provided file name is empty.
  41          * @throws      FileIoException                 If fopen() returns not a file resource
  42          * @return      void
  43          */
  44         public static final function createFrameworkRawFileInputPointer ($fileName) {
  45                 // Some pre-sanity checks...
  46                 if ((is_null($fileName)) || (empty($fileName))) {
  47                         // No filename given
  48                         throw new FileIsEmptyException(NULL, self::EXCEPTION_UNEXPECTED_EMPTY_STRING);
  49                 } elseif (!file_exists($fileName)) {
  50                         // File does not exist!
  51                         throw new FileIoException($fileName, self::EXCEPTION_FILE_NOT_FOUND);
  52                 } elseif (!is_readable($fileName)) {
  53                         // File does not exist!
  54                         throw new FileReadProtectedException($fileName, self::EXCEPTION_FILE_CANNOT_BE_READ);
  55                 }
  56
  57                 // Try to open a handler
  58                 $filePointer = fopen($fileName, 'rb');
  59                 if ((is_null($filePointer)) || ($filePointer === FALSE)) {
  60                         // Something bad happend
  61                         throw new FileIoException($fileName, self::EXCEPTION_FILE_POINTER_INVALID);
  62                 } // END - if
  63
  64                 // Create new instance
  65                 $pointerInstance = new FrameworkRawFileInputPointer();
  66
  67                 // Set file pointer and file name
  68                 $pointerInstance->setPointer($filePointer);
  69                 $pointerInstance->setFileName($fileName);
  70
  71                 // Return the instance
  72                 return $pointerInstance;
  73         }
  74
  75         /**
  76          * Read data a file pointer
  77          *
  78          * @return      mixed   The result of fread()
  79          * @throws      NullPointerException    If the file pointer instance
  80          *                                                                      is not set by setPointer()
  81          * @throws      InvalidResourceException        If there is being set
  82          */
  83         public function readFromFile () {
  84                 if (is_null($this->getPointer())) {
  85                         // Pointer not initialized
  86                         throw new NullPointerException($this, self::EXCEPTION_IS_NULL_POINTER);
  87                 } elseif (!is_resource($this->getPointer())) {
  88                         // Pointer is not a valid resource!
  89                         throw new InvalidResourceException($this, self::EXCEPTION_INVALID_RESOURCE);
  90                 }
  91
  92                 // Read data from the file pointer and return it
  93                 return $this->read(1024);
  94         }
  95
  96         /**
  97          * Reads given amount of bytes from file.
  98          *
  99          * @param       $bytes  Amount of bytes to read
 100          * @return      $data   Data read from file
 101          */
 102         public function read ($bytes) {
 103                 // Try to read given characters
 104                 $data = fread($this->getPointer(), $bytes);
 105
 106                 // Was this successfull?
 107                 assert(is_string($data));
 108
 109                 // Then return it
 110                 return $data;
 111         }
 112
 113         /**
 114          * Analyzes entries in index file. This will count all found (and valid)
 115          * entries, mark invalid as damaged and count gaps ("fragmentation"). If
 116          * only gaps are found, the file is considered as "virgin" (no entries).
 117          *
 118          * @return      void
 119          * @throws      UnsupportedOperationException   If this method is called
 120          */
 121         public function analyzeFile () {
 122                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
 123         }
 124
 125         /**
 126          * Advances to next "block" of bytes
 127          *
 128          * @return      void
 129          * @throws      UnsupportedOperationException   If this method is called
 130          */
 131         public function next () {
 132                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
 133         }
 134
 135         /**
 136          * Checks wether the current entry is valid (not at the end of the file).
 137          * This method will return TRUE if an emptied (nulled) entry has been found.
 138          *
 139          * @return      $isValid        Whether the next entry is valid
 140          * @throws      UnsupportedOperationException   If this method is called
 141          */
 142         public function valid () {
 143                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
 144         }
 145
 146         /**
 147          * Gets current seek position ("key").
 148          *
 149          * @return      $key    Current key in iteration
 150          * @throws      UnsupportedOperationException   If this method is called
 151          */
 152         public function key () {
 153                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
 154         }
 155 }
 156
 157 // [EOF]
 158 ?>