global _indent_counters, _indent_timestamps

function _generic_indent (idx, desc, delta) 
{
  ts = __indent_timestamp ()
  if (! _indent_counters[idx]) _indent_timestamps[idx] = ts

  # pre-increment for positive delta and post-decrement for negative delta
  x = _indent_counters[idx] + (delta > 0 ? delta : 0)
  _indent_counters[idx] += delta

  return sprintf("%6d %s:%-*s", (ts - _indent_timestamps[idx]), desc, (x>0 ? x-1 : 0), "")
}

/**
 * sfunction thread_indent - returns an amount of space with the current task information
 * @delta: the amount of space added/removed for each call
 */
function thread_indent (delta) 
{
  return _generic_indent (tid(), sprintf("%s(%d)", execname(), tid()), delta)
}

/**
 * sfunction indent - returns an amount of space to indent
 * @delta: the amount of space added/removed for each call
 */
function indent(delta){
  return _generic_indent(-1, "",  delta)
}