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
|
<?php
/*
* SCROTT IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* For more information, please refer to UNLICENSE
*/
/* Include database configuration file if it exists */
define("DATABASE_CONFIG_FILE", "dbconfig.php");
is_file(DATABASE_CONFIG_FILE) && require_once DATABASE_CONFIG_FILE;
require_once "class/globals.php";
require_once "class/mysql.class.php";
/*
* This class provides a common interface to various database drivers.
* Scrott provides facilities for interacting with any DBMS that we can
* use in PHP. To provide support for a new DBMS, extend this class and
* implement the abstract functions. Additionally, update the getInstance()
* function in this class so that the new implementation is used under
* appropriate configuration.
*/
abstract class database
{
private static $instance = NULL;
/*
* Call this object's close function while being destructed
*/
public function __destruct()
{
$this->_close();
}
/*
* Return the database instance object, creating it if this is the
* first call to this function. This function will need maintained
* as new DBMSs are supported. This function will throw if the
* database is not configured.
*/
private static function getInstance() : database
{
global $_SCROTT;
if (self::$instance)
return self::$instance;
if (!isset($_SCROTT['conf']))
throw new Exception("Scrott database configuration is missing.");
switch ($_SCROTT['dbEngine'])
{
case "mysql":
$host = $_SCROTT['dbHost'];
$uname = $_SCROTT['dbUname'];
$passwd = $_SCROTT['dbPasswd'];
$dbname = $_SCROTT['dbName'];
self::$instance = new mysql($host, $uname, $passwd, $dbname);
break;
default:
throw new Exception("Problem with Scrott database configuration. Invalid " .
"database engine specified.");
break;
}
return self::$instance;
}
/*
* These functions are to be implemented by DBMS extensions,
* providing a uniform interface to database engines.
*/
protected abstract function _close() : void;
protected abstract function _query(string $query) : array;
protected abstract function _esc(string $str) : string;
/*
* Perform a database query and return the results as an array
* of arrays.
*/
public static function query(string $query) : array
{
return self::getInstance()->_query($query);
}
/*
* Escape a given string for use in a database query
*/
public static function esc(string $str) : string
{
return self::getInstance()->_esc($str);
}
/*
* Check whether Scrott's database config is loaded
*/
public static function checkConfig() : bool
{
try
{
$db = self::getInstance();
}
catch (Exception $e)
{
return false;
}
return true;
}
}
?>
|
