Question

I have some code to upload and download a sound recording from android. The problem i am having is that it appears an extra blank line is appearing in the binary. When this is removed the file plays i would like to know how to stop this line appearing. Below is my upload and download code as well as a print screen of the blank line

Upload code

    mysql_select_db ($database); 

// Make sure the user actually 
// selected and uploaded a file
if (isset($_FILES['image']) && $_FILES['image']['size'] > 0) { 

      $size = $_FILES['image']['size'];
      $type = $_FILES['image']['type'];

      // Temporary file name stored on the server
      $tmpName  = $_FILES['image']['tmp_name'];  

      // Read the file 
      $fp      = fopen($tmpName, 'r');
      $data = fread($fp, filesize($tmpName));
      fclose($fp);

      $data = trim(addslashes($data));

      // Create the query and insert
      // into our database.
      $query = "INSERT INTO media";
      $query .= "(file, file_size, file_type) VALUES ('$data','$size','$type')";
      $results = mysql_query($query, $link);

      $mediaid = mysql_insert_id();

    $gender = $_POST['gender'];
    $cat_id = $_POST['cat'];
    $name = $_POST['name'];
    $lat = $_POST['lat'];
    $lon = $_POST['lon'];
    $user = $_POST['user'];


  $query="INSERT INTO instance (name, gender, cat_id, lon, lat, user_id) VALUES ('$name', '$gender', '$cat_id', '$lon', '$lat', '$user')";
  $result=mysql_query($query);


      $instanceid = mysql_insert_id();

      $query4 = "INSERT INTO media_link";
      $query4 .="(media_id, instance_id) Values ('$mediaid','$instanceid')";
      $results4 = mysql_query($query4, $link);

    }

// Close our MySQL Link
mysql_close($link);
?>

download code

$test2 = @mysql_query("select * from media where media_id = '$media'");
    $result2 = mysql_fetch_array($test2);

header('Content-Type: audio/AMR');
header('Content-Disposition: attachment; filename="ifound.amr"');


    print $result2['file'];
exit;

?>

Blank line that is appearing

Answer 1

Check if your download code has a blank line before the first <?php . Remember to check any file it gets included from as well.

Also change addslashes to mysql_real_escape_string. It might not cause a problem here, but it is security hole.

If you can’t find the root of your problem, you could always try base64_encode / base64_decode. It takes 30% more storage space, but it’s a bullet proof way to store binary data in strings.

Just a tip:

  $fp      = fopen($tmpName, 'r');
  $data = fread($fp, filesize($tmpName));
  fclose($fp);

could be replaced with

  $data = file_get_contents($tmpName)