b167fee3d363d409865c577e24500c5d2e9534d7
[core.git] / inc / classes / main / file_directories / io / class_FrameworkFileInputOutputPointer.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 - 2013 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 FrameworkFileInputOutputPointer extends BaseFileIo implements InputOutputPointer {
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       $fileName       The file name we shall pass to fopen()
40          * @return      void
41          * @throws      FileIsEmptyException            If the given file name is NULL or empty
42          * @throws      FileReadProtectedException      If PHP cannot read an existing file
43          * @throws      FileWriteProtectedException     If PHP cannot write an existing file
44          * @throws      FileIoException                         If fopen() returns not a file resource
45          */
46         public static final function createFrameworkFileInputOutputPointer ($fileName) {
47                 // Some pre-sanity checks...
48                 if ((is_null($fileName)) || (empty($fileName))) {
49                         // No filename given
50                         throw new FileIsEmptyException(NULL, self::EXCEPTION_UNEXPECTED_EMPTY_STRING);
51                 } elseif ((file_exists($fileName)) && (!is_readable($fileName))) {
52                         // File exists but cannot be read
53                         throw new FileReadProtectedException($fileName, self::EXCEPTION_FILE_CANNOT_BE_READ);
54                 } elseif ((file_exists($fileName)) && (!is_writable($fileName))) {
55                         // File exists but cannot be written
56                         throw new FileWriteProtectedException($fileName, self::EXCEPTION_FILE_CANNOT_BE_READ);
57                 }
58
59                 // Try to open a handler
60                 $filePointer = fopen($fileName, 'c+b');
61                 if ((is_null($filePointer)) || ($filePointer === FALSE)) {
62                         // Something bad happend
63                         throw new FileIoException($fileName, self::EXCEPTION_FILE_POINTER_INVALID);
64                 } // END - if
65
66                 // Create new instance
67                 $pointerInstance = new FrameworkFileInputOutputPointer();
68
69                 // Set file pointer and file name
70                 $pointerInstance->setPointer($filePointer);
71                 $pointerInstance->setFileName($fileName);
72
73                 // Return the instance
74                 return $pointerInstance;
75         }
76
77         /**
78          * Read data a file pointer
79          *
80          * @return      mixed   The result of fread()
81          * @throws      NullPointerException    If the file pointer instance
82          *                                                                      is not set by setPointer()
83          * @throws      InvalidResourceException        If there is being set
84          */
85         public function readFromFile () {
86                 if (is_null($this->getPointer())) {
87                         // Pointer not initialized
88                         throw new NullPointerException($this, self::EXCEPTION_IS_NULL_POINTER);
89                 } elseif (!is_resource($this->getPointer())) {
90                         // Pointer is not a valid resource!
91                         throw new InvalidResourceException($this, self::EXCEPTION_INVALID_RESOURCE);
92                 }
93
94                 // Read data from the file pointer and return it
95                 return fread($this->getPointer(), 1024);
96         }
97
98         /**
99          * Write data to a file pointer
100          *
101          * @param       $dataStream             The data stream we shall write to the file
102          * @return      mixed                   Number of writes bytes or FALSE on error
103          * @throws      NullPointerException    If the file pointer instance
104          *                                                                      is not set by setPointer()
105          * @throws      InvalidResourceException        If there is being set
106          *                                                                                      an invalid file resource
107          */
108         public function writeToFile ($dataStream) {
109                 if (is_null($this->getPointer())) {
110                         // Pointer not initialized
111                         throw new NullPointerException($this, self::EXCEPTION_IS_NULL_POINTER);
112                 } elseif (!is_resource($this->getPointer())) {
113                         // Pointer is not a valid resource!
114                         throw new InvalidResourceException($this, self::EXCEPTION_INVALID_RESOURCE);
115                 }
116
117                 // Write data to the file pointer and return written bytes
118                 return fwrite($this->getPointer(), $dataStream, strlen($dataStream));
119         }
120
121         /**
122          * Rewinds to the beginning of the file
123          *
124          * @return      void
125          */
126         public function rewind () {
127                 // Rewind the pointer
128                 assert(rewind($this->getPointer()) === 1);
129         }
130
131         /**
132          * Seeks to given position
133          *
134          * @param       $seekPosition   Seek position in file
135          * @param       $whence                 "Seek mode" (see http://de.php.net/fseek)
136          * @return      void
137          */
138         public function seek ($seekPosition, $whence = SEEK_SET) {
139                 // Move the file pointer
140                 assert(fseek($this->getPointer(), $seekPosition, $whence) === 0);
141         }
142 }
143
144 // [EOF]
145 ?>