|
1
|
|
|
<?php |
|
2
|
|
|
|
|
3
|
|
|
namespace CHMLib\Reader; |
|
4
|
|
|
|
|
5
|
|
|
use Exception; |
|
6
|
|
|
|
|
7
|
|
|
/** |
|
8
|
|
|
* Read data from a file. |
|
9
|
|
|
*/ |
|
10
|
|
|
class FileReader extends Reader |
|
11
|
|
|
{ |
|
12
|
|
|
/** |
|
13
|
|
|
* The file name. |
|
14
|
|
|
* |
|
15
|
|
|
* @var string |
|
16
|
|
|
*/ |
|
17
|
|
|
protected $filename; |
|
18
|
|
|
|
|
19
|
|
|
/** |
|
20
|
|
|
* The file size. |
|
21
|
|
|
* |
|
22
|
|
|
* @var int |
|
23
|
|
|
*/ |
|
24
|
|
|
protected $length; |
|
25
|
|
|
|
|
26
|
|
|
/** |
|
27
|
|
|
* The open file descriptor. |
|
28
|
|
|
* |
|
29
|
|
|
* @var resource |
|
30
|
|
|
*/ |
|
31
|
|
|
protected $fd; |
|
32
|
|
|
|
|
33
|
|
|
/** |
|
34
|
|
|
* Initializes the instance. |
|
35
|
|
|
* |
|
36
|
|
|
* @param string $filename The file name to be read. |
|
37
|
|
|
* |
|
38
|
|
|
* @throws \Exception Throws an Exception in case of errors. |
|
39
|
|
|
*/ |
|
40
|
4 |
|
public function __construct($filename) |
|
41
|
|
|
{ |
|
42
|
4 |
|
$this->filename = $filename; |
|
43
|
4 |
|
if (!is_file($this->filename)) { |
|
44
|
|
|
throw new Exception('File not found: '.$this->filename); |
|
45
|
|
|
} |
|
46
|
4 |
|
if (!is_readable($this->filename)) { |
|
47
|
|
|
throw new Exception('File not readable: '.$this->filename); |
|
48
|
|
|
} |
|
49
|
4 |
|
$this->length = @filesize($this->filename); |
|
50
|
4 |
|
if ($this->length === false || $this->length < 0) { |
|
51
|
|
|
throw new Exception('Failed to retrieve the size of the file '.$this->filename); |
|
52
|
|
|
} |
|
53
|
4 |
|
$this->fd = @fopen($this->filename, 'rb'); |
|
54
|
4 |
|
if ($this->fd === false) { |
|
55
|
|
|
$this->fd = null; |
|
56
|
|
|
throw new Exception('Failed to open file '.$this->filename); |
|
57
|
|
|
} |
|
58
|
4 |
|
} |
|
59
|
|
|
|
|
60
|
|
|
/** |
|
61
|
|
|
* Destruct the instance. |
|
62
|
|
|
*/ |
|
63
|
|
|
public function __destruct() |
|
64
|
|
|
{ |
|
65
|
|
|
if (isset($this->fd)) { |
|
66
|
|
|
@fclose($this->fd); |
|
|
|
|
|
|
67
|
|
|
$this->fd = null; |
|
68
|
|
|
} |
|
69
|
|
|
} |
|
70
|
|
|
|
|
71
|
|
|
/** |
|
72
|
|
|
* Get the file name. |
|
73
|
|
|
* |
|
74
|
|
|
* @return string |
|
75
|
|
|
*/ |
|
76
|
|
|
public function getFilename() |
|
77
|
|
|
{ |
|
78
|
|
|
return $this->filename; |
|
79
|
|
|
} |
|
80
|
|
|
|
|
81
|
|
|
/** |
|
82
|
|
|
* {@inheritdoc} |
|
83
|
|
|
* |
|
84
|
|
|
* @see \CHMLib\Reader\Reader::setPosition() |
|
85
|
|
|
*/ |
|
86
|
29 |
|
public function setPosition($position) |
|
87
|
|
|
{ |
|
88
|
29 |
|
if (@fseek($this->fd, $position, SEEK_SET) !== 0) { |
|
89
|
|
|
throw new Exception('Failed to seek file to to position '.$position); |
|
90
|
|
|
} |
|
91
|
29 |
|
} |
|
92
|
|
|
|
|
93
|
|
|
/** |
|
94
|
|
|
* {@inheritdoc} |
|
95
|
|
|
* |
|
96
|
|
|
* @see \CHMLib\Reader\Reader::getPosition() |
|
97
|
|
|
*/ |
|
98
|
4 |
|
public function getPosition() |
|
99
|
|
|
{ |
|
100
|
4 |
|
$result = @ftell($this->fd); |
|
101
|
4 |
|
if ($result === false) { |
|
102
|
|
|
throw new Exception('Failed to get the current file position'); |
|
103
|
|
|
} |
|
104
|
|
|
|
|
105
|
4 |
|
return $result; |
|
106
|
|
|
} |
|
107
|
|
|
|
|
108
|
|
|
/** |
|
109
|
|
|
* {@inheritdoc} |
|
110
|
|
|
* |
|
111
|
|
|
* @see \CHMLib\Reader\Reader::getLength() |
|
112
|
|
|
*/ |
|
113
|
4 |
|
public function getLength() |
|
114
|
|
|
{ |
|
115
|
4 |
|
return $this->length; |
|
116
|
|
|
} |
|
117
|
|
|
|
|
118
|
|
|
/** |
|
119
|
|
|
* {@inheritdoc} |
|
120
|
|
|
* |
|
121
|
|
|
* @see \CHMLib\Reader\Reader::readString() |
|
122
|
|
|
*/ |
|
123
|
29 |
|
public function readString($length) |
|
124
|
|
|
{ |
|
125
|
29 |
|
if ($length === 0) { |
|
126
|
|
|
$result = ''; |
|
127
|
|
|
} else { |
|
128
|
29 |
|
$result = @fread($this->fd, $length); |
|
129
|
29 |
|
if ($result === false || strlen($result) !== $length) { |
|
130
|
|
|
throw new Exception('Read after end-of-file'); |
|
131
|
|
|
} |
|
132
|
|
|
} |
|
133
|
|
|
|
|
134
|
29 |
|
return $result; |
|
135
|
|
|
} |
|
136
|
|
|
} |
|
137
|
|
|
|
If you suppress an error, we recommend checking for the error condition explicitly: