# Convert a key/value pair to XML.  The value should be +nil+, +String+,
# +Integer+, +Array+, or +ICalPal::RDT+
#
# @param key The key
# @param value The value
# @return [String] The key/value pair in a simple XML format
def xmlify(key, value)
  case value
    # Nil
  when NilClass then "<#{key}/>"

    # Array
  when Array
    # Treat empty arrays as nil values
    xmlify(key, nil) if value[0].nil?

    retval = ''
    value.each { |x| retval += xmlify("#{key}0", x) }
    "<#{key}>#{retval}</#{key}>"

    # Unknown
  else "<#{key}>#{value}</#{key}>"
  end
end

# Get the application icalPal is most likely running in
#
# @return [Integer] The basename of the program whose parent process id is 1 (launchd)
def ancestor
  ppid = Process.ppid

  while (ppid != 1)
    ps = `ps -p #{ppid} -o ppid,command | tail -1`
    ppid = ps[/^[0-9 ]+ /].to_i
  end

  ps[ps.rindex('/') + 1..].chop
end