Extract a common interface for DBLayer classes

Now, the constructors of the various adapter implementations do not
necessarily need to have the same signature anymore.

include/dblayer/common_db.php

@@ -11,32 +11,32 @@
 	exit;
 
 
-// Load the appropriate DB layer class
+// Load and create the appropriate DB adapter (and open/connect to/select db)
 switch ($db_type)
 {
 	case 'mysql':
 	case 'mysqli':
 		require_once PUN_ROOT.'include/dblayer/mysqli.php';
+		$db = new MysqlDBLayer($db_host, $db_username, $db_password, $db_name, $db_prefix, $p_connect);
 		break;
 
 	case 'mysql_innodb':
 	case 'mysqli_innodb':
 		require_once PUN_ROOT.'include/dblayer/mysqli_innodb.php';
+		$db = new MysqlInnodbDBLayer($db_host, $db_username, $db_password, $db_name, $db_prefix, $p_connect);
 		break;
 
 	case 'pgsql':
 		require_once PUN_ROOT.'include/dblayer/pgsql.php';
+		$db = new PgsqlDBLayer($db_host, $db_username, $db_password, $db_name, $db_prefix, $p_connect);
 		break;
 
 	case 'sqlite':
 		require_once PUN_ROOT.'include/dblayer/sqlite.php';
+		$db = new SqliteDBLayer($db_name, $db_prefix, $p_connect);
 		break;
 
 	default:
 		error('\''.$db_type.'\' is not a valid database type. Please check settings in config.php.', __FILE__, __LINE__);
 		break;
 }
-
-
-// Create the database adapter object (and open/connect to/select db)
-$db = new DBLayer($db_host, $db_username, $db_password, $db_name, $db_prefix, $p_connect);

include/dblayer/interface.php

@@ -0,0 +1,70 @@
+<?php
+
+/**
+ * Copyright (C) 2008-2012 FluxBB
+ * based on code by Rickard Andersson copyright (C) 2002-2008 PunBB
+ * License: http://www.gnu.org/licenses/gpl.html GPL version 2 or higher
+ */
+
+interface DBLayer
+{
+	public function start_transaction();
+
+	public function end_transaction();
+
+	public function query($sql, $unbuffered = false);
+
+	public function result($query_id = 0, $row = 0, $col = 0);
+
+	public function fetch_assoc($query_id = 0);
+
+	public function fetch_row($query_id = 0);
+
+	public function has_rows($query_id);
+
+	public function affected_rows();
+
+	public function insert_id();
+
+	public function get_num_queries();
+
+	public function get_saved_queries();
+
+	public function free_result($query_id = false);
+
+	public function escape($str);
+
+	public function error();
+
+	public function close();
+
+	public function get_names();
+
+	public function set_names($names);
+
+	public function get_version();
+
+	public function table_exists($table_name, $no_prefix = false);
+
+	public function field_exists($table_name, $field_name, $no_prefix = false);
+
+	public function index_exists($table_name, $index_name, $no_prefix = false);
+
+	public function create_table($table_name, $schema, $no_prefix = false);
+
+	public function drop_table($table_name, $no_prefix = false);
+
+	public function rename_table($old_table, $new_table, $no_prefix = false);
+
+	public function add_field($table_name, $field_name, $field_type, $allow_null, $default_value = null, $after_field = null, $no_prefix = false);
+
+	public function alter_field($table_name, $field_name, $field_type, $allow_null, $default_value = null, $after_field = null, $no_prefix = false);
+
+	public function drop_field($table_name, $field_name, $no_prefix = false);
+
+	public function add_index($table_name, $index_name, $index_fields, $unique = false, $no_prefix = false);
+
+	public function drop_index($table_name, $index_name, $no_prefix = false);
+
+	public function truncate_table($table_name, $no_prefix = false);
+}

include/dblayer/mysqli.php

@@ -11,7 +11,10 @@
 	exit('This PHP environment doesn\'t have Improved MySQL (mysqli) support built in. Improved MySQL support is required if you want to use a MySQL 4.1 (or later) database to run this forum. Consult the PHP documentation for further assistance.');
 
 
-class DBLayer
+require_once PUN_ROOT.'include/dblayer/interface.php';
+
+
+class MysqlDBLayer implements DBLayer
 {
 	var $prefix;
 	var $link_id;

include/dblayer/mysqli_innodb.php

@@ -11,7 +11,10 @@
 	exit('This PHP environment doesn\'t have Improved MySQL (mysqli) support built in. Improved MySQL support is required if you want to use a MySQL 4.1 (or later) database to run this forum. Consult the PHP documentation for further assistance.');
 
 
-class DBLayer
+require_once PUN_ROOT.'include/dblayer/interface.php';
+
+
+class MysqlInnodbDBLayer implements DBLayer
 {
 	var $prefix;
 	var $link_id;

include/dblayer/pgsql.php

@@ -11,7 +11,10 @@
 	exit('This PHP environment doesn\'t have PostgreSQL support built in. PostgreSQL support is required if you want to use a PostgreSQL database to run this forum. Consult the PHP documentation for further assistance.');
 
 
-class DBLayer
+require_once PUN_ROOT.'include/dblayer/interface.php';
+
+
+class PgsqlDBLayer implements DBLayer
 {
 	var $prefix;
 	var $link_id;

include/dblayer/sqlite.php

@@ -11,7 +11,10 @@
 	exit('This PHP environment doesn\'t have SQLite support built in. SQLite support is required if you want to use a SQLite database to run this forum. Consult the PHP documentation for further assistance.');
 
 
-class DBLayer
+require_once PUN_ROOT.'include/dblayer/interface.php';
+
+
+class SqliteDBLayer implements DBLayer
 {
 	var $prefix;
 	var $link_id;
@@ -31,7 +34,7 @@ class DBLayer
 	);
 
 
-	function __construct($db_host, $db_username, $db_password, $db_name, $db_prefix, $p_connect)
+	function __construct($db_name, $db_prefix, $p_connect)
 	{
 		// Prepend $db_name with the path to the forum root directory
 		$db_name = PUN_ROOT.$db_name;

install.php

@@ -474,32 +474,33 @@ function process_form(the_form)
 }
 else
 {
-	// Load the appropriate DB layer class
+	// Load and create the appropriate DB adapter (and open/connect to/select db)
 	switch ($db_type)
 	{
 		case 'mysqli':
 			require PUN_ROOT.'include/dblayer/mysqli.php';
+			$db = new MysqlDBLayer($db_host, $db_username, $db_password, $db_name, $db_prefix, false);
 			break;
 
 		case 'mysqli_innodb':
 			require PUN_ROOT.'include/dblayer/mysqli_innodb.php';
+			$db = new MysqlInnodbDBLayer($db_host, $db_username, $db_password, $db_name, $db_prefix, false);
 			break;
 
 		case 'pgsql':
 			require PUN_ROOT.'include/dblayer/pgsql.php';
+			$db = new PgsqlDBLayer($db_host, $db_username, $db_password, $db_name, $db_prefix, false);
 			break;
 
 		case 'sqlite':
 			require PUN_ROOT.'include/dblayer/sqlite.php';
+			$db = new SqliteDBLayer($db_name, $db_prefix, false);
 			break;
 
 		default:
 			error(sprintf($lang_install['DB type not valid'], $db_type));
 	}
 
-	// Create the database object (and connect/select db)
-	$db = new DBLayer($db_host, $db_username, $db_password, $db_name, $db_prefix, false);
-
 	// Validate prefix
 	if (strlen($db_prefix) > 0 && (!preg_match('%^[a-zA-Z_][a-zA-Z0-9_]*$%', $db_prefix) || strlen($db_prefix) > 40))
 		error(sprintf($lang_install['Table prefix error'], $db->prefix));