module Listen::Adapter

def _usable_adapter_class
  OPTIMIZED_ADAPTERS.find(&:usable?)
end

def _warn_polling_fallback(options)
  msg = options.fetch(:polling_fallback_message, POLLING_FALLBACK_MESSAGE)
  Listen.adapter_warn("[Listen warning]:\n  #{msg}") if msg
end

def select(options = {})
  Listen.logger.debug 'Adapter: considering polling ...'
  return Polling if options[:force_polling]
  Listen.logger.debug 'Adapter: considering optimized backend...'
  return _usable_adapter_class if _usable_adapter_class
  Listen.logger.debug 'Adapter: falling back to polling...'
  _warn_polling_fallback(options)
  Polling
rescue
  Listen.logger.warn format('Adapter: failed: %s:%s', $ERROR_POSITION.inspect,
                            $ERROR_POSITION * "\n")
  raise
end