Database Connection Library

library/auth.php

+<?php
+
+$db_conn = NULL;
+$db_username = 'lahtp';
+$db_password = 'virtualhostx';
+$db_servername = 'localhost';
+$db_name = 'lahtp_3_web';
+
+function get_db_connection() {
+	global $db_conn;
+	global $db_servername;
+	global $db_username;
+	global $db_password;
+	global $db_name;
+
+	if($db_conn != NULL){ //check if an existing connection is open
+		return $db_conn; //return the existing connection
+	} else { //make a new connection
+		$db_conn = mysqli_connect($db_servername, $db_username, $db_password, $db_name);
+		if(!$db_conn){
+			die("Connection failed: ".mysqli_connect_error());
+		} else {
+			return $db_conn;
+		}
+	}
+}
+
+function do_login($username, $password){
+	$query = "SELECT * FROM lahtp_3_web.auth WHERE username='$username' AND password='$password';";
+	$connection = get_db_connection();
+	$result = mysqli_query($connection, $query);
+	return mysqli_num_rows($result);
+}
\ No newline at end of file

test.php

+<?php
+
+include 'library/auth.php';
+
+if(do_login('sibi', 'passwddord')){
+	echo "Success";
+} else {
+	echo "Failed";
+}
\ No newline at end of file