The podUtil.VisitContainers function in Kubernetes

// ContainerVisitor is called with each container spec, and returns true
// if visiting should continue.
type ContainerVisitor func(container *api.Container, containerType ContainerType) (shouldContinue bool)

// VisitContainers invokes the visitor function with a pointer to every container
// spec in the given pod spec with type set in mask. If visitor returns false,
// visiting is short-circuited. VisitContainers returns true if visiting completes,
// false if visiting was short-circuited.
func VisitContainers(podSpec *api.PodSpec, mask ContainerType, visitor ContainerVisitor) bool {
	if mask&InitContainers != 0 {
		for i := range podSpec.InitContainers {
			if !visitor(&podSpec.InitContainers[i], InitContainers) {
				return false
			}
		}
	}
	if mask&Containers != 0 {
		for i := range podSpec.Containers {
			if !visitor(&podSpec.Containers[i], Containers) {
				return false
			}
		}
	}
	if mask&EphemeralContainers != 0 {
		for i := range podSpec.EphemeralContainers {
			if !visitor((*api.Container)(&podSpec.EphemeralContainers[i].EphemeralContainerCommon), EphemeralContainers) {
				return false
			}
		}
	}
	return true
}