Online PHP editor | output for mvl4C

@ 2018-10-11T03:33:31Z

<html>
<body>
<?php
    if(isset($_POST['login']))
   {
        $username = $_POST['username'];
        $password = $_POST['password'];
        $con = mysqli_connect("localhost","compsec","compsec","mydb");
        $result = mysqli_query($con, "SELECT * FROM `users` WHERE username='$username' AND password='$password'");

        if(mysqli_num_rows($result) == 0)
            echo 'You have entered an invalid username and/or password';
        else
            echo '<h1>Successfully logged in.</h1><p>This text will only be displayed when you have logged in with valid credentials.</p>';
    }
    else
    {
?>
        <form action="" method="post">
            Username: <input type="text" name="username"/><br />
            Password: <input type="password" name="password"/><br />
            <input type="submit" name="login" value="Login"/>
        </form>
<?php
    }
?>
</body>
</html>

Output for 5.6.38, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.4, 8.3.6 - 8.3.7: <html> <body> <form action="" method="post"> Username: <input type="text" name="username"/><br /> Password: <input type="password" name="password"/><br /> <input type="submit" name="login" value="Login"/> </form> </body> </html>
Output for 8.3.5: Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 <html> <body> <form action="" method="post"> Username: <input type="text" name="username"/><br /> Password: <input type="password" name="password"/><br /> <input type="submit" name="login" value="Login"/> </form> </body> </html>

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