# File activesupport/lib/active_support/notifications/fanout.rb, line 122
def initialize
  @mutex = Mutex.new
  @registry = Registry.new
  @all_listeners_for = Concurrent::Map.new
  @groups_for = Concurrent::Map.new
end

# File activesupport/lib/active_support/notifications/fanout.rb, line 398
def all_listeners_for(name)
  # this is correctly done double-checked locking (Concurrent::Map's lookups have volatile semantics)
  @all_listeners_for[name] || @mutex.synchronize do
    # use synchronisation when accessing @registry
    @all_listeners_for[name] ||=
      @registry[name] + @registry.other_subscribers.select { |s| s.subscribed_to?(name) }
  end
end

# File activesupport/lib/active_support/notifications/fanout.rb, line 365
def build_handle(name, id, payload)
  groups = groups_for(name).map do |group_klass, grouped_listeners|
    group_klass.new(grouped_listeners, name, id, payload)
  end

  if groups.empty?
    NullHandle
  else
    Handle.new(name, id, groups, payload)
  end
end

# File activesupport/lib/active_support/notifications/fanout.rb, line 384
def finish(name, id, payload, listeners = nil)
  handle_stack = IsolatedExecutionState[:_fanout_handle_stack]
  handle = handle_stack.pop
  handle.finish_with_values(name, id, payload)
end

# File activesupport/lib/active_support/notifications/fanout.rb, line 407
def listeners_for(name)
  all_listeners_for(name).reject { |s| s.silenced?(name) }
end

# File activesupport/lib/active_support/notifications/fanout.rb, line 411
def listening?(name)
  all_listeners_for(name).any? { |s| !s.silenced?(name) }
end

# File activesupport/lib/active_support/notifications/fanout.rb, line 390
def publish(name, ...)
  iterate_guarding_exceptions(listeners_for(name)) { |s| s.publish(name, ...) }
end

# File activesupport/lib/active_support/notifications/fanout.rb, line 394
def publish_event(event)
  iterate_guarding_exceptions(listeners_for(event.name)) { |s| s.publish_event(event) }
end

# File activesupport/lib/active_support/notifications/fanout.rb, line 377
def start(name, id, payload)
  handle_stack = (IsolatedExecutionState[:_fanout_handle_stack] ||= [])
  handle = build_handle(name, id, payload)
  handle_stack << handle
  handle.start
end

# File activesupport/lib/active_support/notifications/fanout.rb, line 144
def subscribe(pattern = nil, callable = nil, monotonic: false, prepend: false, &block)
  block = ActiveSupport::Ractors.try_shareable_proc(block) if block

  subscriber = Subscribers.new(pattern, callable || block, monotonic)
  @mutex.synchronize do
    case pattern
    when String
      @registry = @registry.add(subscriber, prepend: prepend)
      clear_cache(pattern)
    when NilClass, Regexp
      if prepend
        raise ArgumentError, "Cannot prepend Regex subscribers"
      end
      @registry = @registry.add(subscriber)
      clear_cache
    else
      raise ArgumentError,  "pattern must be specified as a String, Regexp or empty"
    end
  end
  subscriber
end

# File activesupport/lib/active_support/notifications/fanout.rb, line 166
def unsubscribe(subscriber_or_name)
  @mutex.synchronize do
    case subscriber_or_name
    when String
      @registry = @registry.delete_pattern(subscriber_or_name)
      @registry.other_subscribers.each { |sub| sub.unsubscribe!(subscriber_or_name) }
      clear_cache(subscriber_or_name)
    else
      pattern = subscriber_or_name.try(:pattern)
      pattern = nil unless String === pattern

      @registry = @registry.delete(subscriber_or_name)
      clear_cache(pattern)
    end
  end
end

# File activesupport/lib/active_support/notifications/fanout.rb, line 416
def wait
end