For example, the packet library detects the TCP payload type by using
the TCP src/dst port, but in case of the BGP packet, the packet
library will try to parse a TCP ACK packet as a BGP packet, and will
fail to parse.
This patch enables to ignore an empty buffer and fixes this problem.
Signed-off-by: IWASE Yusuke <iwase.yusuke0@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>