/*---------------------------------------------------------------------------*/
static void
init(void)
{
restart_dutycycle(random_rand() % OFF_TIME);
lpp_is_on = 1;
announcement_register_listen_callback(listen_callback);
memb_init(&queued_packets_memb);
list_init(queued_packets_list);
list_init(pending_packets_list);
}
/*---------------------------------------------------------------------------*/
const struct mac_driver *
lpp_init(const struct radio_driver *d)
{
radio = d;
radio->set_receive_function(input_packet);
restart_dutycycle(random_rand() % OFF_TIME);
lpp_is_on = 1;
announcement_register_listen_callback(listen_callback);
memb_init(&queued_packets_memb);
list_init(queued_packets_list);
list_init(pending_packets_list);
return &lpp_driver;
}
/**
* Read a packet from the underlying radio driver. If the incoming
* packet is a probe packet and the sender of the probe matches the
* destination address of the queued packet (if any), the queued packet
* is sent.
*/
static void
input_packet(void)
{
struct lpp_hdr hdr;
clock_time_t reception_time;
reception_time = clock_time();
if(!NETSTACK_FRAMER.parse()) {
printf("lpp input_packet framer error\n");
}
memcpy(&hdr, packetbuf_dataptr(), sizeof(struct lpp_hdr));;
packetbuf_hdrreduce(sizeof(struct lpp_hdr));
/* PRINTF("got packet type %d\n", hdr->type);*/
if(hdr.type == TYPE_PROBE) {
struct announcement_msg adata;
/* Register the encounter with the sending node. We now know the
neighbor's phase. */
register_encounter(&hdr.sender, reception_time);
/* Parse incoming announcements */
memcpy(&adata, packetbuf_dataptr(),
MIN(packetbuf_datalen(), sizeof(adata)));
#if 0
PRINTF("%d.%d: probe from %d.%d with %d announcements\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
hdr.sender.u8[0], hdr.sender.u8[1], adata->num);
if(adata.num / sizeof(struct announcement_data) > sizeof(struct announcement_msg)) {
/* Sanity check. The number of announcements is too large -
corrupt packet has been received. */
return 0;
}
for(i = 0; i < adata.num; ++i) {
/* PRINTF("%d.%d: announcement %d: %d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
adata->data[i].id,
adata->data[i].value);*/
announcement_heard(&hdr.sender,
adata.data[i].id,
adata.data[i].value);
}
#endif /* 0 */
/* Go through the list of packets to be sent to see if any of
them match the sender of the probe, or if they are a
broadcast packet that should be sent. */
if(list_length(queued_packets_list) > 0) {
struct queue_list_item *i;
for(i = list_head(queued_packets_list); i != NULL; i = list_item_next(i)) {
const rimeaddr_t *receiver;
uint8_t sent;
sent = 0;
receiver = queuebuf_addr(i->packet, PACKETBUF_ADDR_RECEIVER);
if(rimeaddr_cmp(receiver, &hdr.sender) ||
rimeaddr_cmp(receiver, &rimeaddr_null)) {
queuebuf_to_packetbuf(i->packet);
#if WITH_PENDING_BROADCAST
if(i->broadcast_flag == BROADCAST_FLAG_NONE ||
i->broadcast_flag == BROADCAST_FLAG_SEND) {
i->num_transmissions = 1;
NETSTACK_RADIO.send(queuebuf_dataptr(i->packet),
queuebuf_datalen(i->packet));
sent = 1;
PRINTF("%d.%d: got a probe from %d.%d, sent packet to %d.%d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
hdr.sender.u8[0], hdr.sender.u8[1],
receiver->u8[0], receiver->u8[1]);
} else {
PRINTF("%d.%d: got a probe from %d.%d, did not send packet\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
hdr.sender.u8[0], hdr.sender.u8[1]);
}
#else /* WITH_PENDING_BROADCAST */
i->num_transmissions = 1;
NETSTACK_RADIO.send(queuebuf_dataptr(i->packet),
queuebuf_datalen(i->packet));
PRINTF("%d.%d: got a probe from %d.%d, sent packet to %d.%d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
hdr.sender.u8[0], hdr.sender.u8[1],
receiver->u8[0], receiver->u8[1]);
#endif /* WITH_PENDING_BROADCAST */
/* off();*/
/* Attribute the energy spent on listening for the probe
to this packet transmission. */
compower_accumulate(&i->compower);
/* If the packet was not a broadcast packet, we dequeue it
now. Broadcast packets should be transmitted to all
neighbors, and are dequeued by the dutycycling function
instead, after the appropriate time. */
if(!rimeaddr_cmp(receiver, &rimeaddr_null)) {
if(detect_ack()) {
remove_queued_packet(i, 1);
} else {
remove_queued_packet(i, 0);
}
#if WITH_PROBE_AFTER_TRANSMISSION
/* Send a probe packet to catch any reply from the other node. */
restart_dutycycle(PROBE_AFTER_TRANSMISSION_TIME);
#endif /* WITH_PROBE_AFTER_TRANSMISSION */
#if WITH_STREAMING
if(is_streaming) {
ctimer_set(&stream_probe_timer, STREAM_PROBE_TIME,
send_stream_probe, NULL);
}
#endif /* WITH_STREAMING */
}
if(sent) {
turn_radio_off();
}
#if WITH_ACK_OPTIMIZATION
if(packetbuf_attr(PACKETBUF_ATTR_RELIABLE) ||
packetbuf_attr(PACKETBUF_ATTR_ERELIABLE)) {
/* We're sending a packet that needs an ACK, so we keep
the radio on in anticipation of the ACK. */
turn_radio_on();
}
#endif /* WITH_ACK_OPTIMIZATION */
}
}
}
} else if(hdr.type == TYPE_DATA) {
turn_radio_off();
if(!rimeaddr_cmp(&hdr.receiver, &rimeaddr_null)) {
if(!rimeaddr_cmp(&hdr.receiver, &rimeaddr_node_addr)) {
/* Not broadcast or for us */
PRINTF("%d.%d: data not for us from %d.%d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
hdr.sender.u8[0], hdr.sender.u8[1]);
return;
}
packetbuf_set_addr(PACKETBUF_ADDR_RECEIVER, &hdr.receiver);
}
packetbuf_set_addr(PACKETBUF_ADDR_SENDER, &hdr.sender);
PRINTF("%d.%d: got data from %d.%d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
hdr.sender.u8[0], hdr.sender.u8[1]);
/* Accumulate the power consumption for the packet reception. */
compower_accumulate(¤t_packet);
/* Convert the accumulated power consumption for the received
packet to packet attributes so that the higher levels can
keep track of the amount of energy spent on receiving the
packet. */
compower_attrconv(¤t_packet);
/* Clear the accumulated power consumption so that it is ready
for the next packet. */
compower_clear(¤t_packet);
#if WITH_PENDING_BROADCAST
if(rimeaddr_cmp(&hdr.receiver, &rimeaddr_null)) {
/* This is a broadcast packet. Check the list of pending
packets to see if we are currently sending a broadcast. If
so, we refrain from sending our broadcast until one sleep
cycle period, so that the other broadcaster will have
finished sending. */
struct queue_list_item *i;
for(i = list_head(queued_packets_list); i != NULL; i = list_item_next(i)) {
/* If the packet is a broadcast packet that is not yet
ready to be sent, we do not send it. */
if(i->broadcast_flag == BROADCAST_FLAG_PENDING) {
PRINTF("Someone else is sending, pending -> waiting\n");
set_broadcast_flag(i, BROADCAST_FLAG_WAITING);
}
}
}
#endif /* WITH_PENDING_BROADCAST */
#if WITH_PROBE_AFTER_RECEPTION
/* XXX send probe after receiving a packet to facilitate data
streaming. We must first copy the contents of the packetbuf into
a queuebuf to avoid overwriting the data with the probe packet. */
if(rimeaddr_cmp(&hdr.receiver, &rimeaddr_node_addr)) {
struct queuebuf *q;
q = queuebuf_new_from_packetbuf();
if(q != NULL) {
send_probe();
queuebuf_to_packetbuf(q);
queuebuf_free(q);
}
}
#endif /* WITH_PROBE_AFTER_RECEPTION */
#if WITH_ADAPTIVE_OFF_TIME
off_time = LOWEST_OFF_TIME;
restart_dutycycle(off_time);
#endif /* WITH_ADAPTIVE_OFF_TIME */
NETSTACK_MAC.input();
}
}
/**
*
* Send a packet. This function builds a complete packet with an LPP
* header and queues the packet. When a probe is heard (in the
* read_packet() function), and the sender of the probe matches the
* receiver of the queued packet, the queued packet is sent.
*
* ACK packets are treated differently from other packets: if a node
* sends a packet that it expects to be ACKed, the sending node keeps
* its radio on for some time after sending its packet. So we do not
* need to wait for a probe packet: we just transmit the ACK packet
* immediately.
*
*/
static void
send_packet(mac_callback_t sent, void *ptr)
{
struct lpp_hdr hdr;
clock_time_t timeout;
uint8_t is_broadcast = 0;
rimeaddr_copy(&hdr.sender, &rimeaddr_node_addr);
rimeaddr_copy(&hdr.receiver, packetbuf_addr(PACKETBUF_ADDR_RECEIVER));
if(rimeaddr_cmp(&hdr.receiver, &rimeaddr_null)) {
is_broadcast = 1;
}
hdr.type = TYPE_DATA;
packetbuf_hdralloc(sizeof(struct lpp_hdr));
memcpy(packetbuf_hdrptr(), &hdr, sizeof(struct lpp_hdr));
packetbuf_compact();
packetbuf_set_attr(PACKETBUF_ATTR_MAC_ACK, 1);
{
int hdrlen = NETSTACK_FRAMER.create();
if(hdrlen == 0) {
/* Failed to send */
mac_call_sent_callback(sent, ptr, MAC_TX_ERR_FATAL, 0);
return;
}
}
PRINTF("%d.%d: queueing packet to %d.%d, channel %d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
hdr.receiver.u8[0], hdr.receiver.u8[1],
packetbuf_attr(PACKETBUF_ATTR_CHANNEL));
#if WITH_ACK_OPTIMIZATION
if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) == PACKETBUF_ATTR_PACKET_TYPE_ACK) {
/* Send ACKs immediately. */
NETSTACK_RADIO.send(packetbuf_hdrptr(), packetbuf_totlen());
mac_call_sent_callback(sent, ptr, MAC_TX_OK, 1);
return;
}
#endif /* WITH_ACK_OPTIMIZATION */
#if WITH_ADAPTIVE_OFF_TIME
off_time = LOWEST_OFF_TIME;
restart_dutycycle(off_time);
#endif /* WITH_ADAPTIVE_OFF_TIME */
{
struct queue_list_item *i;
i = memb_alloc(&queued_packets_memb);
if(i != NULL) {
i->sent_callback = sent;
i->sent_callback_ptr = ptr;
i->num_transmissions = 0;
i->packet = queuebuf_new_from_packetbuf();
if(i->packet == NULL) {
memb_free(&queued_packets_memb, i);
printf("null packet\n");
mac_call_sent_callback(sent, ptr, MAC_TX_ERR, 0);
return;
} else {
if(is_broadcast) {
timeout = PACKET_LIFETIME;
#if WITH_PENDING_BROADCAST
/* We set the broadcast state of the packet to be
waiting. This means that the packet is waiting for our
next probe to be sent. Our next probe is used to check if
there are any neighbors currently broadcasting a
packet. If so, we will get a broadcast packet in response
to our probe. If no broadcast packet is received in
response to our probe, we mark the packet as ready to be
sent. */
set_broadcast_flag(i, BROADCAST_FLAG_WAITING);
PRINTF("-> waiting\n");
#endif /* WITH_PENDING_BROADCAST */
} else {
timeout = UNICAST_TIMEOUT;
#if WITH_PENDING_BROADCAST
i->broadcast_flag = BROADCAST_FLAG_NONE;
#endif /* WITH_PENDING_BROADCAST */
}
ctimer_set(&i->removal_timer, timeout,
remove_queued_old_packet_callback, i);
/* Wait for a probe packet from a neighbor. The actual packet
transmission is handled by the read_packet() function,
which receives the probe from the neighbor. */
turn_radio_on_for_neighbor(&hdr.receiver, i);
}
} else {
printf("i == NULL\n");
mac_call_sent_callback(sent, ptr, MAC_TX_ERR, 0);
}
}
}