cgroup

type CGroup interface {
	// Adds the context to this group.
	// Returns true if the underlying context is not yet done and this context was added to the active set, even briefly.
	Add(c context.Context) (ok bool)

	// Starts or retrieves the prior context for this CGroup.
	// This will be already canceled if no contexts were added.
	Start() context.Context

	// Wait ensures this group has started, and then blocks until the [context.Context] is completed, returning its cause if not the default [context.Canceled].
	Wait() error

	// Go runs the given method as part of this group.
	// It will only start after Start() has been called with valid contexts.
	// Any returned error will cancel the group's [context.Context] directly, rather than with any provided cause.
	// Returns true if the method has a chance of running.
	Go(func(c context.Context) error) bool

	// Halt runs the given method when this group may be about to shut down.
	// It is passed a channel which is closed if the group restarts.
	// It will only run after a successful Start() and then a potential shutdown.
	// Any returned error will cancel the group's [context.Context] directly, rather than with any provided cause.
	// Returns true if the method has a chance of running.
	Halt(func(c context.Context, resume <-chan struct{}) error) bool
}