int receive(int port_num, const char *buffer, int len) {
static int pkt_id = 0;
auto packet = new_packet_ptr(port_num, pkt_id++, len,
PacketBuffer(2048, buffer, len));
ELOGGER->packet_in(*packet);
input_buffer.push_front(std::move(packet));
return 0;
}
int
SimpleSwitch::receive(int port_num, const char *buffer, int len) {
static int pkt_id = 0;
// this is a good place to call this, because blocking this thread will not
// block the processing of existing packet instances, which is a requirement
if (do_swap() == 0) {
check_queueing_metadata();
}
// we limit the packet buffer to original size + 512 bytes, which means we
// cannot add more than 512 bytes of header data to the packet, which should
// be more than enough
auto packet = new_packet_ptr(port_num, pkt_id++, len,
bm::PacketBuffer(len + 512, buffer, len));
BMELOG(packet_in, *packet);
PHV *phv = packet->get_phv();
// many current P4 programs assume this
// it is also part of the original P4 spec
phv->reset_metadata();
// setting standard metadata
phv->get_field("standard_metadata.ingress_port").set(port_num);
// using packet register 0 to store length, this register will be updated for
// each add_header / remove_header primitive call
packet->set_register(PACKET_LENGTH_REG_IDX, len);
phv->get_field("standard_metadata.packet_length").set(len);
Field &f_instance_type = phv->get_field("standard_metadata.instance_type");
f_instance_type.set(PKT_INSTANCE_TYPE_NORMAL);
if (phv->has_field("intrinsic_metadata.ingress_global_timestamp")) {
phv->get_field("intrinsic_metadata.ingress_global_timestamp")
.set(get_ts().count());
}
input_buffer.push_front(std::move(packet));
return 0;
}
