Android Tutorial Connect Android to MySQL Database Tutorial

<?

$databasehost = "localhost";
$databasename = "dbname";
$databaseusername ="username";
$databasepassword = "password";

$con = mysql_connect($databasehost,$databaseusername,$databasepassword) or die(mysql_error());
mysql_select_db($databasename) or die(mysql_error());
$query = file_get_contents("php://input"); 
$sth = mysql_query($query);

if (mysql_errno()) { 
    header("HTTP/1.1 500 Internal Server Error");
    echo $query.'\n';
    echo mysql_error(); 
}
else
{
    $rows = array();
    while($r = mysql_fetch_assoc($sth)) {
        $rows[] = $r;
    }
    //This line below is changed from json_encode to __json_encode
    print __json_encode($rows);
}

function __json_encode( $data ) {            
    if( is_array($data) || is_object($data) ) { 
        $islist = is_array($data) && ( empty($data) || array_keys($data) === range(0,count($data)-1) ); 
        
        if( $islist ) { 
            $json = '[' . implode(',', array_map('__json_encode', $data) ) . ']'; 
        } else { 
            $items = Array(); 
            foreach( $data as $key => $value ) { 
                $items[] = __json_encode("$key") . ':' . __json_encode($value); 
            } 
            $json = '{' . implode(',', $items) . '}'; 
        } 
    } elseif( is_string($data) ) { 
        # Escape non-printable or Non-ASCII characters. 
        # I also put the \\ character first, as suggested in comments on the 'addclashes' page. 
        $string = '"' . addcslashes($data, "\\\"\n\r\t/" . chr(8) . chr(12)) . '"'; 
        $json    = ''; 
        $len    = strlen($string); 
        # Convert UTF-8 to Hexadecimal Codepoints. 
        for( $i = 0; $i < $len; $i++ ) { 
            
            $char = $string[$i]; 
            $c1 = ord($char); 
            
            # Single byte; 
            if( $c1 <128 ) { 
                $json .= ($c1 > 31) ? $char : sprintf("\\u%04x", $c1); 
                continue; 
            } 
            
            # Double byte 
            $c2 = ord($string[++$i]); 
            if ( ($c1 & 32) === 0 ) { 
                $json .= sprintf("\\u%04x", ($c1 - 192) * 64 + $c2 - 128); 
                continue; 
            } 
            
            # Triple 
            $c3 = ord($string[++$i]); 
            if( ($c1 & 16) === 0 ) { 
                $json .= sprintf("\\u%04x", (($c1 - 224) <<12) + (($c2 - 128) << 6) + ($c3 - 128)); 
                continue; 
            } 
                
            # Quadruple 
            $c4 = ord($string[++$i]); 
            if( ($c1 & 8 ) === 0 ) { 
                $u = (($c1 & 15) << 2) + (($c2>>4) & 3) - 1; 
            
                $w1 = (54<<10) + ($u<<6) + (($c2 & 15) << 2) + (($c3>>4) & 3); 
                $w2 = (55<<10) + (($c3 & 15)<<6) + ($c4-128); 
                $json .= sprintf("\\u%04x\\u%04x", $w1, $w2); 
            } 
        } 
    } else { 
        # int, floats, bools, null 
        $json = strtolower(var_export( $data, true )); 
    } 
    return $json; 
} 
?>