Function bpf_peers_present

freebsd/net/bpf.h:435–444

u_int	 bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int);

static __inline int
bpf_peers_present(struct bpf_if *bpf)
{
	struct bpf_if_ext *ext;

	ext = (struct bpf_if_ext *)bpf;
	if (!CK_LIST_EMPTY(&ext->bif_dlist))
		return (1);
	return (0);
}

#define	BPF_TAP(_ifp,_pkt,_pktlen) do {				\
	if (bpf_peers_present((_ifp)->if_bpf))			\