ip_pktinfo(p1, p2, p3 = v3)
public
Returns new ancillary data for IP_PKTINFO.
If spec_dst is not given, addr is used.
IP_PKTINFO is not standard.
Supported platform: GNU/Linux
addr = Addrinfo.ip("127.0.0.1")
ifindex = 0
spec_dst = Addrinfo.ip("127.0.0.1")
p Socket::AncillaryData.ip_pktinfo(addr, ifindex, spec_dst)
static VALUE
ancillary_s_ip_pktinfo(int argc, VALUE *argv, VALUE self)
{
VALUE v_addr, v_ifindex, v_spec_dst;
unsigned int ifindex;
struct sockaddr_in sa;
struct in_pktinfo pktinfo;
rb_scan_args(argc, argv, "21", &v_addr, &v_ifindex, &v_spec_dst);
SockAddrStringValue(v_addr);
ifindex = NUM2UINT(v_ifindex);
if (NIL_P(v_spec_dst))
v_spec_dst = v_addr;
else
SockAddrStringValue(v_spec_dst);
memset(&pktinfo, 0, sizeof(pktinfo));
memset(&sa, 0, sizeof(sa));
if (RSTRING_LEN(v_addr) != sizeof(sa))
rb_raise(rb_eArgError, "addr size different to AF_INET sockaddr");
memcpy(&sa, RSTRING_PTR(v_addr), sizeof(sa));
if (sa.sin_family != AF_INET)
rb_raise(rb_eArgError, "addr is not AF_INET sockaddr");
memcpy(&pktinfo.ipi_addr, &sa.sin_addr, sizeof(pktinfo.ipi_addr));
pktinfo.ipi_ifindex = ifindex;
memset(&sa, 0, sizeof(sa));
if (RSTRING_LEN(v_spec_dst) != sizeof(sa))
rb_raise(rb_eArgError, "spec_dat size different to AF_INET sockaddr");
memcpy(&sa, RSTRING_PTR(v_spec_dst), sizeof(sa));
if (sa.sin_family != AF_INET)
rb_raise(rb_eArgError, "spec_dst is not AF_INET sockaddr");
memcpy(&pktinfo.ipi_spec_dst, &sa.sin_addr, sizeof(pktinfo.ipi_spec_dst));
return ancdata_new(AF_INET, IPPROTO_IP, IP_PKTINFO, rb_str_new((char *)&pktinfo, sizeof(pktinfo)));
}