1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
|
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
* CodeIgniter
*
* An open source application development framework for PHP 4.3.2 or newer
*
* @package CodeIgniter
* @author ExpressionEngine Dev Team
* @copyright Copyright (c) 2006, EllisLab, Inc.
* @license http://codeigniter.com/user_guide/license.html
* @link http://codeigniter.com
* @since Version 1.0
* @filesource
*/
// ------------------------------------------------------------------------
/**
* Database Cache Class
*
* @category Database
* @author ExpressionEngine Dev Team
* @link http://codeigniter.com/user_guide/database/
*/
class CI_DB_Cache {
var $CI;
var $db; // allows passing of db object so that multiple database connections and returned db objects can be supported
/**
* Constructor
*
* Grabs the CI super object instance so we can access it.
*
*/
function CI_DB_Cache(&$db)
{
// Assign the main CI object to $this->CI
// and load the file helper since we use it a lot
$this->CI =& get_instance();
$this->db =& $db;
$this->CI->load->helper('file');
}
// --------------------------------------------------------------------
/**
* Set Cache Directory Path
*
* @access public
* @param string the path to the cache directory
* @return bool
*/
function check_path($path = '')
{
if ($path == '')
{
if ($this->db->cachedir == '')
{
return $this->db->cache_off();
}
$path = $this->db->cachedir;
}
// Add a trailing slash to the path if needed
$path = preg_replace("/(.+?)\/*$/", "\\1/", $path);
if ( ! is_dir($path) OR ! is_really_writable($path))
{
// If the path is wrong we'll turn off caching
return $this->db->cache_off();
}
$this->db->cachedir = $path;
return TRUE;
}
// --------------------------------------------------------------------
/**
* Retrieve a cached query
*
* The URI being requested will become the name of the cache sub-folder.
* An MD5 hash of the SQL statement will become the cache file name
*
* @access public
* @return string
*/
function read($sql)
{
if ( ! $this->check_path())
{
return $this->db->cache_off();
}
$uri = ($this->CI->uri->segment(1) == FALSE) ? 'default.' : $this->CI->uri->segment(1).'+';
$uri .= ($this->CI->uri->segment(2) == FALSE) ? 'index' : $this->CI->uri->segment(2);
$filepath = $uri.'/'.md5($sql);
if (FALSE === ($cachedata = read_file($this->db->cachedir.$filepath)))
{
return FALSE;
}
return unserialize($cachedata);
}
// --------------------------------------------------------------------
/**
* Write a query to a cache file
*
* @access public
* @return bool
*/
function write($sql, $object)
{
if ( ! $this->check_path())
{
return $this->db->cache_off();
}
$uri = ($this->CI->uri->segment(1) == FALSE) ? 'default.' : $this->CI->uri->segment(1).'+';
$uri .= ($this->CI->uri->segment(2) == FALSE) ? 'index' : $this->CI->uri->segment(2);
$dir_path = $this->db->cachedir.$uri.'/';
$filename = md5($sql);
if ( ! @is_dir($dir_path))
{
if ( ! @mkdir($dir_path, DIR_WRITE_MODE))
{
return FALSE;
}
@chmod($dir_path, DIR_WRITE_MODE);
}
if (write_file($dir_path.$filename, serialize($object)) === FALSE)
{
return FALSE;
}
@chmod($dir_path.$filename, DIR_WRITE_MODE);
return TRUE;
}
// --------------------------------------------------------------------
/**
* Delete cache files within a particular directory
*
* @access public
* @return bool
*/
function delete($segment_one = '', $segment_two = '')
{
if ($segment_one == '')
{
$segment_one = ($this->CI->uri->segment(1) == FALSE) ? 'default' : $this->CI->uri->segment(1);
}
if ($segment_two == '')
{
$segment_two = ($this->CI->uri->segment(2) == FALSE) ? 'index' : $this->CI->uri->segment(2);
}
$dir_path = $this->db->cachedir.$segment_one.'+'.$segment_two.'/';
delete_files($dir_path, TRUE);
}
// --------------------------------------------------------------------
/**
* Delete all existing cache files
*
* @access public
* @return bool
*/
function delete_all()
{
delete_files($this->db->cachedir, TRUE);
}
}
/* End of file DB_cache.php */
/* Location: ./system/database/DB_cache.php */
|