Help Fatal error: Call to undefined function asql()

Hey please me fix i get this error here is my code

<?php
$hash=asql($_GET['hash']);
if (isset($_SESSION['userid'])) {
print "You can't request password recovery link while logged in";
} else {
if ($hash!='') {
$gethash=$gps_black->q("SELECT * FROM passwd_recovery WHERE hash='{$hash}'") or die(mysql_error());
if ($gps_black->n($gethash)==0) {
print "Link you entered is invalid. Please check the link and try again.";
} else {
if (isset($_POST['newpasswd'])) {
if ($_POST['newpasswd'] == $_POST['cnewpasswd']) {
$getuserid=$gps_black->f($gethash);
$username=$getuserid['username'];
$userpass = md5($_POST['newpasswd']);
$gps_black->q("UPDATE users SET userpass='{$userpass}' WHERE username='{$username}'") or die(mysql_error());
$gps_black->q("DELETE FROM passwd_recovery WHERE username='{$username}'") or die(mysql_error());
print "<center>Password changed.<br>Please <a href='index.php?place=login'>Login</a> with your new password.</center>";
} else {
print "<center>The two new passwords must match. <br><a href='history.go(-1)'>Go Back</a> and re-enter password</a></center>";
}
} else {
print "<center><form action='index.php?place=forgot&hash={$hash}' method=POST>
New Password<br><input type=password name=newpasswd><br>
Confirm New Password<br><input type=password name=cnewpasswd><br>
<input type=submit value='Change password'>";
}
}
} else {
if (isset($_POST['username']) && isset($_POST['email'])) {
$username=asql($_POST['username']);
$email=asql($_POST['email']);
$getuser = $gps_black->q("SELECT * FROM users WHERE username='{$username}' AND email='{$email}'") or die(mysql_error());
if($gps_black->n($getuser)==0) {
print "<center>We can't find used with such details. <br><a href='history.go(-1)'>Go Back</a> and re-enter username and email</a></center>";
} else {
$hash=md5($username . $email . rand(5, 1000));
mail($email, "Password recovery link",
"Please follow link below to recover your password.
http://".$_SERVER['HTTP_HOST']."/index.php?place=forgot&hash={$hash}

Offers4Rewards Administration.", "From: ");
$gps_black->q("INSERT INTO passwd_recovery VALUES('','{$username}','{$hash}')") or die(mysql_error());
print "Password recovery link have been sent to your email address";
}
}
print "<center><form action='index.php?place=forgot' method=POST>
Your Username<br><input type=text name=username><br>
Your Email<br><input type=text name=email><br>
<input type=submit value='Request link'>";
}
}



?>

here is link to error http://cashcove.info/places/forgot.php please tell me how to fix

 

asql(); function does not exists in php