php mysql login not working [duplicate]

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• When to use single quotes, double quotes, and backticks? 6 answers

I'm trying to write a php script to login to a website. I'm very new to all of this and have been looking at it for probably about 2 days now. I've tried to write a script that I've compiled from a couple of sources online to try and do what I want to do. But for some reason it isn't working. I think it is disagreeing somewhere around the if(!empty($_POST)) { part but I can't see exactly what it is. I'm using Brackets to write it all and it keeps having issues with the } to close the if statement, but I can't see where they're not balanced.

<?php
function db_connect() {
    static $connection;
    if(!isset($connection)) {
        $config = parse_ini_file('../private/config.ini');
        $connection = mysqli_connect('localhost',$config['username'],$config['password'],$config['dbname']);
    }
        if($connection === false) {
            return mysqli_connect_error();
        }
        return $connection;
}

function db_query($query) {
    $connection = db_connect();
    $result = mysqli_query($connection, $query);
    return $result;
}

function db_error() {
    $connection = db_connect();
    return mysqli_error($connection);
}

$submitted_username = '';    

if(!empty($_POST)) {
    $username = $_POST['username']
    $query = db_query("SELECT * From users where username = $username)";
    $result = mysqli_query($connection, $query);
    $login_ok = false;
    if($result) {
        $check_password = hash('sha256', $_POST['password'] . $result['salt'];
        for($round = 0; $round < 65536; $round++) {
            $check_password = hash('sha256', $check_password . $row['salt']);
        }
       if($check_password === $row['password']) { 
            $login_ok = true; 
        }
                               }}
if($login_ok) {
    unset($row['salt']); 
    unset($row['password']); 
    $_SESSION['user'] = $row; 
    header("Location: Dashboard.php"); 
    die("Redirecting to: Dashboard.php"); 
} else {
    print("Login Failed."); 
    $submitted_username = htmlentities($_POST['username'], ENT_QUOTES, 'UTF-8'); 
}

?>