Read Variable Length Quantity

// Using JavaScript (node.js) to Read Variable Length Quantity
// See - http://en.wikipedia.org/wiki/Variable-length_quantity for more information

Utils = {}
Utils.arrayToHex = function(ar) {
  for (var i=0;i<ar.length;i++) {
    ar[i] = (ar[i].toString(16) == 0) ? "00" : ar[i].toString(16);
  } 
  return "0x" + ar.join('');
}

Utils.readVarLen = function(val) {
  var buffer = [];
  buffer.push((val & 0x7F));
  val = (val >> 7)
  while (val > 0) {
    buffer.push(0x80 + (val & 0x7f))
    val = (val >> 7)
  }
  return Utils.arrayToHex(buffer.reverse());
}
sys.puts(Utils.readVarLen(0x00000000)); 
sys.puts(Utils.readVarLen(0x00000040)); 
sys.puts(Utils.readVarLen(0x00000080)); 
sys.puts(Utils.readVarLen(0x00004000));
sys.puts(Utils.readVarLen(0x00003FFF));
sys.puts(Utils.readVarLen(0x0FFFFFFF));