\PDO

<?php
/** File PDO.class.php			*
 * 	Porting of native PHP 5.1 PDO	*
 *	  object usable with PHP 4.X.X	*
 *	  and PHP 5.0.X version.		*
 * ------------------------------------ *
 *(C) Andrea Giammarchi [2005/10/19]	*
 * ____________________________________ */

// check and preserve native PDO driver, for PHP4 or PHP 5.0 users
if(!class_exists('PDO')) {

	// SUPPORTED STATIC ENVIROMENT VARIABLES
	define('PDO_ATTR_SERVER_VERSION', 4);	// server version
	define('PDO_ATTR_CLIENT_VERSION', 5);	// client version
	define('PDO_ATTR_SERVER_INFO', 6);	// server informations
	define('PDO_ATTR_PERSISTENT', 12);	// connection mode, persistent or normal

	// SUPPORTED STATIC PDO FETCH MODE VARIABLES
		define('PDO_FETCH_ASSOC', 2);		// such mysql_fetch_assoc
	define('PDO_FETCH_NUM', 3);		// such mysql_fetch_row
	define('PDO_FETCH_BOTH', 4);		// such mysql_fetch_array
	define('PDO_FETCH_OBJ', 5);		// such mysql_fetch_object

	// UNSUPPORTED STATIC PDO FETCH MODE VARIABLES
		define('PDO_FETCH_LAZY', 1);		// usable but not supported, default is PDO_FETCH_BOTH and will be used
	define('PDO_FETCH_BOUND', 6);		// usable but not supported, default is PDO_FETCH_BOTH and will be used

	/**
	 * Class PDO
		 * 	PostgreSQL, SQLITE and MYSQL PDO support for PHP 4.X.X or PHP 5.0.X users, compatible with PHP 5.1.0 (RC1).
		 *
		 * DESCRIPTION [directly from http://us2.php.net/manual/en/ref.pdo.php]
	 * 	The PHP Data Objects (PDO) extension defines a lightweight, consistent interface for accessing databases in PHP.
		 *	  Each database driver that implements the PDO interface can expose database-specific features as regular extension functions.
		 *	  Note that you cannot perform any database functions using the PDO extension by itself;
		 *	  you must use a database-specific PDO driver to access a database server.
		 *
		 * HOW TO USE
		 * 	To know how to use PDO driver and all its methods visit php.net wonderful documentation.
		 *	  http://us2.php.net/manual/en/ref.pdo.php
		 *	  In this class some methods are not available and actually this porting is only for MySQL, SQLITE and PostgreSQL.
		 *
		 * LIMITS
		 * 	For some reasons ( time and php used version with this class ) some PDO methods are not availables and
		 *	  someother are not totally supported.
		 *
		 *	  PDO :: UNSUPPORTED METHODS:
		 *	  	- beginTransaction 	[ mysql 3 has not transaction and manage them is possible only with a direct BEGIN
		 *			  			  or COMMIT query ]
		 *			  - commit
		 *			  - rollback
		 *
		 *	  PDO :: NOT TOTALLY SUPPORTED METHODS:
		 *	  	- getAttribute		[ accepts only PDO_ATTR_SERVER_INFO, PDO_ATTR_SERVER_VERSION,
		 *			  			  PDO_ATTR_CLIENT_VERSION and PDO_ATTR_PERSISTENT attributes ]
		 *			  - setAttribute		[ supports only PDO_ATTR_PERSISTENT modification ]
		 *			  - lastInsertId		[ only fo PostgreSQL , returns only pg_last_oid ]
		 *
		 *	  - - - - - - - - - - - - - - - - - - - -
		 *
		 *	  PDOStatement :: UNSUPPORTED METHODS:
		 *	  	- bindColumn 		[ is not possible to undeclare a variable and using global scope is not
		 *			  			  really a good idea ]
		 *
		 *	  PDOStatement :: NOT TOTALLY SUPPORTED METHODS:
		 *	  	- getAttribute		[ accepts only PDO_ATTR_SERVER_INFO, PDO_ATTR_SERVER_VERSION,
		 *			  			  PDO_ATTR_CLIENT_VERSION and PDO_ATTR_PERSISTENT attributes ]
		 *			  - setAttribute		[ supports only PDO_ATTR_PERSISTENT modification ]
		 *			  - setFetchMode		[ supports only PDO_FETCH_NUM, PDO_FETCH_ASSOC, PDO_FETCH_OBJ and
		 *			  			  PDO_FETCH_BOTH database reading mode ]
	 * ---------------------------------------------
	 * @Compatibility	>= PHP 4
	 * @Dependencies	PDO_mysql.class.php
		 *					  PDO_sqlite.class.php
		 *					  PDOStatement_mysql.class.php
		 *					  PDOStatement_sqlite.class.php
	 * @Author		Andrea Giammarchi
	 * @Site		http://www.devpro.it/
	 * @Mail		andrea [ at ] 3site [ dot ] it
	 * @Date		2005/10/13
	 * @LastModified	2005/12/01 21:40
	 * @Version		0.1b - tested, supports only PostgreSQL, MySQL or SQLITE databases
	 */
	class PDO {

		/** Modified on 2005/12/01 to support new PDO constants on PHP 5.1.X */
		const FETCH_ASSOC = PDO_FETCH_ASSOC;
		const FETCH_NUM = PDO_FETCH_NUM;
		const FETCH_BOTH = PDO_FETCH_BOTH;
		const FETCH_OBJ = PDO_FETCH_OBJ;
		const FETCH_LAZY = PDO_FETCH_LAZY;
		const FETCH_BOUND = PDO_FETCH_BOUND;
		const ATTR_SERVER_VERSION = PDO_ATTR_SERVER_VERSION;
		const ATTR_CLIENT_VERSION = PDO_ATTR_CLIENT_VERSION;
		const ATTR_SERVER_INFO = PDO_ATTR_SERVER_INFO;
		const ATTR_PERSISTENT = PDO_ATTR_PERSISTENT;


		/**
		 * 'Private' variables:
		 *	__driver:PDO_*		Dedicated PDO database class
		 */
		var $__driver;

		/**
		 * Public constructor
		 *	http://us2.php.net/manual/en/function.pdo-construct.php
		 */
		function PDO($string_dsn, $string_username = '', $string_password = '', $array_driver_options = null) {
			$con = &$this->__getDNS($string_dsn);
			if($con['dbtype'] === 'mysql') {
				require_once('PDO_mysql.class.php');
				if(isset($con['port']))
					$con['host'] .= ':'.$con['port'];
				$this->__driver = new PDO_mysql(
					$con['host'],
					$con['dbname'],
					$string_username,
					$string_password
				);
			}
			elseif($con['dbtype'] === 'sqlite2' || $con['dbtype'] === 'sqlite') {
				require_once('PDO_sqlite.class.php');
				$this->__driver = new PDO_sqlite($con['dbname']);
			}
			elseif($con['dbtype'] === 'pgsql') {
				require_once('PDO_pgsql.class.php');
				$string_dsn = "host={$con['host']} dbname={$con['dbname']} user={$string_username} password={$string_password}";
				if(isset($con['port']))
					$string_dsn .= " port={$con['port']}";
				$this->__driver = new PDO_pgsql($string_dsn);
			}
		}

		/** UNSUPPORTED
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-begintransaction.php
		 */
		function beginTransaction() {
			$this->__driver->beginTransaction();
		}

		/** NOT NATIVE BUT MAYBE USEFULL FOR PHP < 5.1 PDO DRIVER
		 * Public method
				 * Calls database_close function.
		 *	this->close( Void ):Boolean
				 * @Return	Boolean		True on success, false otherwise
		 */
		function close() {
			return $this->__driver->close();
		}

		/** UNSUPPORTED
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-commit.php
		 */
		function commit() {
			$this->__driver->commit();
		}

		/**
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-exec.php
		 */
		function exec($query) {
			return $this->__driver->exec($query);
		}

		/**
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-errorcode.php
		 */
		function errorCode() {
			return $this->__driver->errorCode();
		}

		/**
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-errorinfo.php
		 */
		function errorInfo() {
			return $this->__driver->errorInfo();
		}

		/** NOT TOTALLY UNSUPPORTED
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-getattribute.php
		 */
		function getAttribute($attribute) {
			return $this->__driver->getAttribute($attribute);
		}

		/**
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-lastinsertid.php
		 */
		function lastInsertId() {
			return $this->__driver->lastInsertId();
		}

		/**
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-prepare.php
		 */
		function prepare($query, $array = Array()) {
			return $this->__driver->prepare($query, $array = Array());
		}

		/**
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-query.php
		 */
		function query($query) {
			return $this->__driver->query($query);
		}

		/**
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-quote.php
		 */
		function quote($string) {
			return $this->__driver->quote($string);
		}

		/** UNSUPPORTED
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-rollback.php
		 */
		function rollBack() {
			$this->__driver->rollBack();
		}

		/** NOT TOTALLY UNSUPPORTED
		 * Public method
		 *	http://us2.php.net/manual/en/function.pdo-setattribute.php
		 */
		function setAttribute($attribute, $mixed) {
			return $this->__driver->setAttribute($attribute, $mixed);
		}

		// PRIVATE METHOD [uncommented]
				function __getDNS(&$string) {
			$result = array();
			$pos = strpos($string, ':');
			$parameters = explode(';', substr($string, ($pos + 1)));
			$result['dbtype'] = strtolower(substr($string, 0, $pos));
			for($a = 0, $b = count($parameters); $a < $b; $a++) {
				$tmp = explode('=', $parameters[$a]);
				if(count($tmp) == 2)
					$result[$tmp[0]] = $tmp[1];
				else
					$result['dbname'] = $parameters[$a];
			}
			return $result;
		}
	}
}
// If you have PHP 5.1 but want to test this class, declare PDO variables as _PDO variables
else {
	/**
	 * Class _PDO
		 * (C) Andrea Giammarchi
		 * Please read PDO class comments to know more
	 */
	class _PDO {
		const FETCH_ASSOC = PDO::FETCH_ASSOC;
		const FETCH_NUM = PDO::FETCH_NUM;
		const FETCH_BOTH = PDO::FETCH_BOTH;
		const FETCH_OBJ = PDO::FETCH_OBJ;
		const FETCH_LAZY = PDO::FETCH_LAZY;
		const FETCH_BOUND = PDO::FETCH_BOUND;
		const ATTR_SERVER_VERSION = PDO::ATTR_SERVER_VERSION;
		const ATTR_CLIENT_VERSION = PDO::ATTR_CLIENT_VERSION;
		const ATTR_SERVER_INFO = PDO::ATTR_SERVER_INFO;
		const ATTR_PERSISTENT = PDO::ATTR_PERSISTENT;
		var $__driver;
		function _PDO($string_dsn, $string_username = '', $string_password = '', $array_driver_options = null) {
			$con = &$this->__getDNS($string_dsn);
			if($con['dbtype'] === 'mysql') {
				require_once('PDO_mysql.class.php');
				if(isset($con['port']))
					$con['host'] .= ':'.$con['port'];
				$this->__driver = new PDO_mysql(
					$con['host'],
					$con['dbname'],
					$string_username,
					$string_password
				);
			}
			elseif($con['dbtype'] === 'sqlite2' || $con['dbtype'] === 'sqlite') {
				require_once('PDO_sqlite.class.php');
				$this->__driver = new PDO_sqlite($con['dbname']);
			}
			elseif($con['dbtype'] === 'pgsql') {
				require_once('PDO_pgsql.class.php');
				$string_dsn = "host={$con['host']} dbname={$con['dbname']} user={$string_username} password={$string_password}";
				if(isset($con['port']))
					$string_dsn .= " port={$con['port']}";
				$this->__driver = new PDO_pgsql($string_dsn);
			}
		}
		function beginTransaction() {
			$this->__driver->beginTransaction();
		}
		function close() {
			return $this->__driver->close();
		}
		function commit() {
			$this->__driver->commit();
		}
		function exec($query) {
			return $this->__driver->exec($query);
		}
		function errorCode() {
			return $this->__driver->errorCode();
		}
		function errorInfo() {
			return $this->__driver->errorInfo();
		}
		function getAttribute($attribute) {
			return $this->__driver->getAttribute($attribute);
		}
		function lastInsertId() {
			return $this->__driver->lastInsertId();
		}
		function prepare($query, $array = Array()) {
			return $this->__driver->prepare($query, $array = Array());
		}
		function query($query) {
			return $this->__driver->query($query);
		}
		function quote($string) {
			return $this->__driver->quote($string);
		}
		function rollBack() {
			$this->__driver->rollBack();
		}
		function setAttribute($attribute, $mixed) {
			return $this->__driver->setAttribute($attribute, $mixed);
		}
				function __getDNS(&$string) {
			$result = array();
			$pos = strpos($string, ':');
			$parameters = explode(';', substr($string, ($pos + 1)));
			$result['dbtype'] = strtolower(substr($string, 0, $pos));
			for($a = 0, $b = count($parameters); $a < $b; $a++) {
				$tmp = explode('=', $parameters[$a]);
				if(count($tmp) == 2)
					$result[$tmp[0]] = $tmp[1];
				else
					$result['dbname'] = $parameters[$a];
			}
			return $result;
		}
	}
}
?>