mcr/libpcap — pull request #18 by ani-sinha (2012-12-11 00:07:09+00:00)
Title: check for TP_STATUS_VLAN_VALID to differentiate between tagged and untagged packet

Linux kernel 3.0 uses TP_STATUS_VLAN_VALID flag in packet
auxilliary data (aux->tp_status) to indicate a packet tagged
with a valid vlan ID 0 with another packet that is not
vlan tagged. Use this flag to check for the presence of
a vlan tagged packet. Also be careful not to cause any
breakage when libpcap is compiled against a newer kernel
(>=3.0) and used on top of an older kernel that does not
use this flag.

Signed-off-by: Ani Sinha