/*---------------------------------------------------------------------------*/
static void
send_packet(mac_callback_t sent, void *ptr)
{
struct rdc_buf_list *q;
struct neighbor_queue *n;
static uint8_t initialized = 0;
static uint16_t seqno;
const rimeaddr_t *addr = packetbuf_addr(PACKETBUF_ADDR_RECEIVER);
if(!initialized) {
initialized = 1;
/* Initialize the sequence number to a random value as per 802.15.4. */
seqno = random_rand();
}
if(seqno == 0) {
/* PACKETBUF_ATTR_MAC_SEQNO cannot be zero, due to a pecuilarity
in framer-802154.c. */
seqno++;
}
packetbuf_set_attr(PACKETBUF_ATTR_MAC_SEQNO, seqno++);
/* Look for the neighbor entry */
n = neighbor_queue_from_addr(addr);
if(n == NULL) {
/* Allocate a new neighbor entry */
n = memb_alloc(&neighbor_memb);
if(n != NULL) {
/* Init neighbor entry */
rimeaddr_copy(&n->addr, addr);
n->transmissions = 0;
n->collisions = 0;
n->deferrals = 0;
/* Init packet list for this neighbor */
LIST_STRUCT_INIT(n, queued_packet_list);
/* Add neighbor to the list */
list_add(neighbor_list, n);
}
}
if(n != NULL) {
/* Add packet to the neighbor's queue */
q = memb_alloc(&packet_memb);
if(q != NULL) {
q->ptr = memb_alloc(&metadata_memb);
if(q->ptr != NULL) {
q->buf = queuebuf_new_from_packetbuf();
if(q->buf != NULL) {
struct qbuf_metadata *metadata = (struct qbuf_metadata *)q->ptr;
/* Neighbor and packet successfully allocated */
if(packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS) == 0) {
/* Use default configuration for max transmissions */
metadata->max_transmissions = CSMA_MAX_MAC_TRANSMISSIONS;
} else {
metadata->max_transmissions =
packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS);
}
metadata->sent = sent;
metadata->cptr = ptr;
if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) ==
PACKETBUF_ATTR_PACKET_TYPE_ACK) {
list_push(n->queued_packet_list, q);
} else {
list_add(n->queued_packet_list, q);
}
/* If q is the first packet in the neighbor's queue, send asap */
if(list_head(n->queued_packet_list) == q) {
ctimer_set(&n->transmit_timer, 0, transmit_packet_list, n);
}
return;
}
memb_free(&metadata_memb, q->ptr);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
memb_free(&packet_memb, q);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
/* The packet allocation failed. Remove and free neighbor entry if empty. */
if(list_length(n->queued_packet_list) == 0) {
list_remove(neighbor_list, n);
memb_free(&neighbor_memb, n);
}
PRINTF("csma: could not allocate packet, dropping packet\n");
} else {
PRINTF("csma: could not allocate neighbor, dropping packet\n");
}
mac_call_sent_callback(sent, ptr, MAC_TX_ERR, 1);
}
/*---------------------------------------------------------------------------*/
static void
packet_sent(void *ptr, int status, int num_transmissions)
{
struct neighbor_queue *n;
struct rdc_buf_list *q;
n = ptr;
if(n == NULL) {
return;
}
/* Find out what packet this callback refers to */
for(q = list_head(n->queued_packet_list);
q != NULL; q = list_item_next(q)) {
#if CETIC_6LBR_MULTI_RADIO
if(queuebuf_attr(q->buf, PACKETBUF_ATTR_MAC_SEQNO) ==
packetbuf_attr(PACKETBUF_ATTR_MAC_SEQNO) &&
(q->ptr == NULL ||
((struct qbuf_metadata *)q->ptr)->ifindex == multi_radio_input_ifindex)) {
#else
if(queuebuf_attr(q->buf, PACKETBUF_ATTR_MAC_SEQNO) ==
packetbuf_attr(PACKETBUF_ATTR_MAC_SEQNO)) {
#endif
break;
}
}
if(q == NULL) {
PRINTF("csma: seqno %d not found\n",
packetbuf_attr(PACKETBUF_ATTR_MAC_SEQNO));
return;
} else if(q->ptr == NULL) {
PRINTF("csma: no metadata\n");
return;
}
switch(status) {
case MAC_TX_OK:
tx_ok(q, n, num_transmissions);
break;
case MAC_TX_NOACK:
noack(q, n, num_transmissions);
break;
case MAC_TX_COLLISION:
collision(q, n, num_transmissions);
break;
case MAC_TX_DEFERRED:
break;
default:
tx_done(status, q, n);
break;
}
}
/*---------------------------------------------------------------------------*/
static void
send_packet(mac_callback_t sent, void *ptr)
{
struct rdc_buf_list *q;
struct neighbor_queue *n;
const linkaddr_t *addr = packetbuf_addr(PACKETBUF_ADDR_RECEIVER);
/* Look for the neighbor entry */
n = neighbor_queue_from_addr(addr);
if(n == NULL) {
/* Allocate a new neighbor entry */
n = memb_alloc(&neighbor_memb);
if(n != NULL) {
/* Init neighbor entry */
linkaddr_copy(&n->addr, addr);
n->transmissions = 0;
n->collisions = CSMA_MIN_BE;
/* Init packet list for this neighbor */
LIST_STRUCT_INIT(n, queued_packet_list);
/* Add neighbor to the list */
list_add(neighbor_list, n);
}
}
if(n != NULL) {
/* Add packet to the neighbor's queue */
if(list_length(n->queued_packet_list) < CSMA_MAX_PACKET_PER_NEIGHBOR) {
q = memb_alloc(&packet_memb);
if(q != NULL) {
q->ptr = memb_alloc(&metadata_memb);
if(q->ptr != NULL) {
q->buf = queuebuf_new_from_packetbuf();
if(q->buf != NULL) {
struct qbuf_metadata *metadata = (struct qbuf_metadata *)q->ptr;
/* Neighbor and packet successfully allocated */
if(packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS) == 0) {
/* Use default configuration for max transmissions */
metadata->max_transmissions = CSMA_MAX_MAX_FRAME_RETRIES + 1;
} else {
metadata->max_transmissions =
packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS);
}
metadata->sent = sent;
metadata->cptr = ptr;
#if CETIC_6LBR_MULTI_RADIO
metadata->ifindex = multi_radio_output_ifindex;
#endif
#if PACKETBUF_WITH_PACKET_TYPE
if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) ==
PACKETBUF_ATTR_PACKET_TYPE_ACK) {
list_push(n->queued_packet_list, q);
} else
#endif
{
list_add(n->queued_packet_list, q);
}
PRINTF("csma: send_packet, queue length %d, free packets %d\n",
list_length(n->queued_packet_list), memb_numfree(&packet_memb));
/* If q is the first packet in the neighbor's queue, send asap */
if(list_head(n->queued_packet_list) == q) {
schedule_transmission(n);
}
return;
}
memb_free(&metadata_memb, q->ptr);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
memb_free(&packet_memb, q);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
/* The packet allocation failed. Remove and free neighbor entry if empty. */
if(list_length(n->queued_packet_list) == 0) {
list_remove(neighbor_list, n);
memb_free(&neighbor_memb, n);
}
} else {
PRINTF("csma: Neighbor queue full\n");
}
PRINTF("csma: could not allocate packet, dropping packet\n");
csma_packet_overflow++;
} else {
PRINTF("csma: could not allocate neighbor, dropping packet\n");
csma_neighbor_overflow++;
}
mac_call_sent_callback(sent, ptr, MAC_TX_ERR, 1);
}
/*---------------------------------------------------------------------------*/
static void
input_packet(void)
{
csma_received_packets++;
NETSTACK_LLSEC.input();
}
/*---------------------------------------------------------------------------*/
static void
packet_sent(void *ptr, int status, int num_transmissions)
{
struct neighbor_queue *n;
struct rdc_buf_list *q;
struct qbuf_metadata *metadata;
clock_time_t time = 0;
mac_callback_t sent;
void *cptr;
int num_tx;
int backoff_transmissions;
n = ptr;
if(n == NULL) {
return;
}
switch(status) {
case MAC_TX_OK:
case MAC_TX_NOACK:
n->transmissions++;
break;
case MAC_TX_COLLISION:
n->collisions++;
break;
case MAC_TX_DEFERRED:
n->deferrals++;
break;
}
for(q = list_head(n->queued_packet_list);
q != NULL; q = list_item_next(q)) {
if(queuebuf_attr(q->buf, PACKETBUF_ATTR_MAC_SEQNO) ==
packetbuf_attr(PACKETBUF_ATTR_MAC_SEQNO)) {
break;
}
}
if(q != NULL) {
metadata = (struct qbuf_metadata *)q->ptr;
if(metadata != NULL) {
sent = metadata->sent;
cptr = metadata->cptr;
#if CSMA_ADVANCED
num_tx = n->transmissions + n->collisions/8;
#else
num_tx = n->transmissions;
#endif
if(status == MAC_TX_COLLISION ||
status == MAC_TX_NOACK) {
/* If the transmission was not performed because of a
collision or noack, we must retransmit the packet. */
switch(status) {
case MAC_TX_COLLISION:
PRINTF("csma: rexmit collision %d\n", n->transmissions);
break;
case MAC_TX_NOACK:
PRINTF("csma: rexmit noack %d\n", n->transmissions);
break;
case MAC_TX_DEFERRED:
PRINTF("phase deferred\n");
break;
default:
PRINTF("csma: rexmit err %d, %d\n", status, n->transmissions);
}
#if CSMA_ADVANCED
int i;
/* The retransmission time must be proportional to the channel
check interval of the underlying radio duty cycling layer. */
time = default_timebase() / 3;
/* The retransmission time uses a linear backoff so that the
interval between the transmissions increase with each
retransmit. */
backoff_transmissions = 1;
for(i=0; i<num_tx-1; i++) {
backoff_transmissions *= 3;
}
/* Clamp the number of backoffs so that we don't get a too long
timeout here, since that will delay all packets in the
queue. */
if(backoff_transmissions > 3 * 3) {
backoff_transmissions = 3 * 3;
}
time = default_timebase() + (random_rand() % (backoff_transmissions * time));
if(num_tx < metadata->max_transmissions) {
#else
/* The retransmission time must be proportional to the channel
check interval of the underlying radio duty cycling layer. */
time = default_timebase();
/* The retransmission time uses a linear backoff so that the
interval between the transmissions increase with each
retransmit. */
backoff_transmissions = n->transmissions + 1;
/* Clamp the number of backoffs so that we don't get a too long
timeout here, since that will delay all packets in the
queue. */
if(backoff_transmissions > 3) {
backoff_transmissions = 3;
}
time = time + (random_rand() % (backoff_transmissions * time));
if(n->transmissions < metadata->max_transmissions) {
#endif
PRINTF("csma: retransmitting with time %lu %p\n", time, q);
ctimer_set(&n->transmit_timer, time,
transmit_packet_list, n);
/* This is needed to correctly attribute energy that we spent
transmitting this packet. */
queuebuf_update_attr_from_packetbuf(q->buf);
} else {
if(!rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER),
&rimeaddr_null)) {
LOG_FROM_PACKETBUF("csma: drop with status %d after %d transmissions, %d collisions",
status, n->transmissions, n->collisions);
}
free_packet(n, q);
mac_call_sent_callback(sent, cptr, status, num_tx);
}
} else {
if(status == MAC_TX_OK) {
if(!rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER),
&rimeaddr_null)) {
LOG_FROM_PACKETBUF("csma: rexmit ok after %d transmissions, %d collisions", n->transmissions, n->collisions);
}
} else {
//LOG_FROM_PACKETBUF("csma: rexmit failed %d: %d\n", n->transmissions, status);
}
free_packet(n, q);
mac_call_sent_callback(sent, cptr, status, num_tx);
}
}
}
}
/*---------------------------------------------------------------------------*/
static void
send_packet(mac_callback_t sent, void *ptr)
{
struct rdc_buf_list *q;
struct neighbor_queue *n;
static uint16_t seqno;
const rimeaddr_t *addr = packetbuf_addr(PACKETBUF_ADDR_RECEIVER);
if(seqno == 0) {
/* PACKETBUF_ATTR_MAC_SEQNO cannot be zero, due to a pecuilarity
in framer-802154.c. */
seqno++;
}
packetbuf_set_attr(PACKETBUF_ATTR_MAC_SEQNO, seqno++);
/* Look for the neighbor entry */
n = neighbor_queue_from_addr(addr);
if(n == NULL) {
/* Allocate a new neighbor entry */
n = memb_alloc(&neighbor_memb);
if(n != NULL) {
/* Init neighbor entry */
rimeaddr_copy(&n->addr, addr);
n->transmissions = 0;
n->collisions = 0;
n->deferrals = 0;
/* Init packet list for this neighbor */
LIST_STRUCT_INIT(n, queued_packet_list);
/* Add neighbor to the list */
list_add(neighbor_list, n);
}
}
if(n != NULL) {
/* Add packet to the neighbor's queue */
q = memb_alloc(&packet_memb);
if(q != NULL) {
q->ptr = memb_alloc(&metadata_memb);
if(q->ptr != NULL) {
q->buf = queuebuf_new_from_packetbuf();
if(q->buf != NULL) {
struct qbuf_metadata *metadata = (struct qbuf_metadata *)q->ptr;
/* Neighbor and packet successfully allocated */
if(packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS) == 0) {
/* Use default configuration for max transmissions */
metadata->max_transmissions = CSMA_MAX_MAC_TRANSMISSIONS;
} else {
metadata->max_transmissions =
packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS);
}
metadata->sent = sent;
metadata->cptr = ptr;
if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) ==
PACKETBUF_ATTR_PACKET_TYPE_ACK) {
list_push(n->queued_packet_list, q);
} else {
list_add(n->queued_packet_list, q);
}
/* If q is the first packet in the neighbor's queue, send asap */
if(list_head(n->queued_packet_list) == q) {
ctimer_set(&n->transmit_timer, 0, transmit_packet_list, n);
}
return;
}
memb_free(&metadata_memb, q->ptr);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
memb_free(&packet_memb, q);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
/* The packet allocation failed. Remove and free neighbor entry if empty. */
if(list_length(n->queued_packet_list) == 0) {
list_remove(neighbor_list, n);
memb_free(&neighbor_memb, n);
}
PRINTF("csma: could not allocate packet, dropping packet\n");
} else {
PRINTF("csma: could not allocate neighbor, dropping packet\n");
}
mac_call_sent_callback(sent, ptr, MAC_TX_ERR, 1);
}
/*---------------------------------------------------------------------------*/
static void
input_packet(void)
{
NETSTACK_NETWORK.input();
}
/*---------------------------------------------------------------------------*/
static int
on(void)
{
return NETSTACK_RDC.on();
}
/*---------------------------------------------------------------------------*/
static int
off(int keep_radio_on)
{
return NETSTACK_RDC.off(keep_radio_on);
}
/*---------------------------------------------------------------------------*/
static unsigned short
channel_check_interval(void)
{
if(NETSTACK_RDC.channel_check_interval) {
return NETSTACK_RDC.channel_check_interval();
}
return 0;
}
/*---------------------------------------------------------------------------*/
static void
init(void)
{
memb_init(&packet_memb);
memb_init(&metadata_memb);
memb_init(&neighbor_memb);
}
/*---------------------------------------------------------------------------*/
static void
send_packet(mac_callback_t sent, void *ptr)
{
struct rdc_buf_list *q;
struct neighbor_queue *n;
const linkaddr_t *addr = packetbuf_addr(PACKETBUF_ADDR_RECEIVER);
/* Look for the neighbor entry */
n = neighbor_queue_from_addr(addr);
if(n == NULL) {
/* Allocate a new neighbor entry */
n = memb_alloc(&neighbor_memb);
if(n != NULL) {
/* Init neighbor entry */
linkaddr_copy(&n->addr, addr);
n->transmissions = 0;
n->collisions = 0;
n->deferrals = 0;
/* Init packet list for this neighbor */
LIST_STRUCT_INIT(n, queued_packet_list);
/* Add neighbor to the list */
list_add(neighbor_list, n);
}
}
if(n != NULL) {
/* Add packet to the neighbor's queue */
if(list_length(n->queued_packet_list) < CSMA_MAX_PACKET_PER_NEIGHBOR) {
q = memb_alloc(&packet_memb);
if(q != NULL) {
q->ptr = memb_alloc(&metadata_memb);
if(q->ptr != NULL) {
q->buf = queuebuf_new_from_packetbuf();
if(q->buf != NULL) {
struct qbuf_metadata *metadata = (struct qbuf_metadata *)q->ptr;
/* Neighbor and packet successfully allocated */
if(packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS) == 0) {
/* Use default configuration for max transmissions */
metadata->max_transmissions = CSMA_MAX_MAC_TRANSMISSIONS;
} else {
metadata->max_transmissions =
packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS);
}
metadata->sent = sent;
metadata->cptr = ptr;
#if PACKETBUF_WITH_PACKET_TYPE
if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) ==
PACKETBUF_ATTR_PACKET_TYPE_ACK) {
list_push(n->queued_packet_list, q);
} else
#endif
{
list_add(n->queued_packet_list, q);
}
PRINTF("csma: send_packet, queue length %d, free packets %d\n",
list_length(n->queued_packet_list), memb_numfree(&packet_memb));
/* If q is the first packet in the neighbor's queue, send asap */
if(list_head(n->queued_packet_list) == q) {
ctimer_set(&n->transmit_timer, 0, transmit_packet_list, n);
}
return;
}
memb_free(&metadata_memb, q->ptr);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
memb_free(&packet_memb, q);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
/* The packet allocation failed. Remove and free neighbor entry if empty. */
if(list_length(n->queued_packet_list) == 0) {
list_remove(neighbor_list, n);
memb_free(&neighbor_memb, n);
}
} else {
PRINTF("csma: Neighbor queue full\n");
}
PRINTF("csma: could not allocate packet, dropping packet\n");
} else {
PRINTF("csma: could not allocate neighbor, dropping packet\n");
}
mac_call_sent_callback(sent, ptr, MAC_TX_ERR, 1);
}
/*---------------------------------------------------------------------------*/
static void
send_packet(mac_callback_t sent, void *ptr)
{
struct rdc_buf_list *q;
struct neighbor_queue *n;
static uint16_t seqno;
packetbuf_set_attr(PACKETBUF_ATTR_MAC_SEQNO, seqno++);
/* If the packet is a broadcast, do not allocate a queue
entry. Instead, just send it out. */
if(!rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER),&rimeaddr_null)) {
const rimeaddr_t *addr = packetbuf_addr(PACKETBUF_ADDR_RECEIVER);
/* Look for the neighbor entry */
n = neighbor_queue_from_addr(addr);
if(n == NULL) {
/* Allocate a new neighbor entry */
n = memb_alloc(neighbor_memb);
if(n != NULL) {
/* Init neighbor entry */
rimeaddr_copy(&n->addr, addr);
n->transmissions = 0;
n->collisions = 0;
n->deferrals = 0;
/* Init packet list for this neighbor */
n->queued_packet_list = ttc_list_create((const char*)n->queued_packet_list);
ttc_list_init(n->queued_packet_list, (const char*)n->queued_packet_list);
/* Add neighbor to the list */
list_add(neighbor_list, n);
}
}
if(n != NULL) {
/* Add packet to the neighbor's queue */
q = memb_alloc(packet_memb);
if(q != NULL) {
q->ptr = memb_alloc(metadata_memb);
if(q->ptr != NULL) {
q->buf = queuebuf_new_from_packetbuf();
if(q->buf != NULL) {
struct qbuf_metadata *metadata = (struct qbuf_metadata *)q->ptr;
/* Neighbor and packet successfully allocated */
if(packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS) == 0) {
/* Use default configuration for max transmissions */
metadata->max_transmissions = CSMA_MAX_MAC_TRANSMISSIONS;
} else {
metadata->max_transmissions =
packetbuf_attr(PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS);
}
metadata->sent = sent;
metadata->cptr = ptr;
if(packetbuf_attr(PACKETBUF_ATTR_PACKET_TYPE) ==
PACKETBUF_ATTR_PACKET_TYPE_ACK) {
list_push(n->queued_packet_list, q);
} else {
list_add(n->queued_packet_list, q);
}
/* If q is the first packet in the neighbor's queue, send asap */
if(list_head(n->queued_packet_list) == q) {
ctimer_set(&n->transmit_timer, 0, transmit_packet_list, n);
}
return;
}
memb_free(metadata_memb, q->ptr);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
memb_free(packet_memb, q);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
/* The packet allocation failed. Remove and free neighbor entry if empty. */
if(list_length(n->queued_packet_list) == 0) {
list_remove(neighbor_list, n);
memb_free(neighbor_memb, n);
}
PRINTF("csma: could not allocate packet, dropping packet\n");
} else {
PRINTF("csma: could not allocate neighbor, dropping packet\n");
}
mac_call_sent_callback(sent, ptr, MAC_TX_ERR, 1);
} else {
PRINTF("csma: send broadcast\n");
NETSTACK_RDC.send(sent, ptr);
}
}
/*---------------------------------------------------------------------------*/
static uint8_t
send_packet(struct net_buf *buf, mac_callback_t sent, bool last_fragment, void *ptr)
{
struct rdc_buf_list *q;
struct neighbor_queue *n;
static uint8_t initialized = 0;
static uint16_t seqno;
const linkaddr_t *addr = packetbuf_addr(buf, PACKETBUF_ADDR_RECEIVER);
if (!buf) {
UIP_LOG("csma: send_packet(): net_buf is NULL, cannot send packet");
return 0;
}
if(!initialized) {
initialized = 1;
/* Initialize the sequence number to a random value as per 802.15.4. */
seqno = random_rand();
}
if(seqno == 0) {
/* PACKETBUF_ATTR_MAC_SEQNO cannot be zero, due to a pecuilarity
in framer-802154.c. */
seqno++;
}
packetbuf_set_attr(buf, PACKETBUF_ATTR_MAC_SEQNO, seqno++);
/* Look for the neighbor entry */
n = neighbor_queue_from_addr(buf, addr);
if(n == NULL) {
/* Allocate a new neighbor entry */
n = memb_alloc(&neighbor_memb);
if(n != NULL) {
/* Init neighbor entry */
linkaddr_copy(&n->addr, addr);
n->transmissions = 0;
n->collisions = 0;
n->deferrals = 0;
/* Init packet list for this neighbor */
LIST_STRUCT_INIT(n, queued_packet_list);
/* Add neighbor to the list */
list_add(uip_neighbor_list(buf), n);
}
}
if(n != NULL) {
/* Add packet to the neighbor's queue */
if(list_length(n->queued_packet_list) < CSMA_MAX_PACKET_PER_NEIGHBOR) {
q = memb_alloc(&packet_memb);
if(q != NULL) {
q->ptr = memb_alloc(&metadata_memb);
if(q->ptr != NULL) {
q->buf = queuebuf_new_from_packetbuf(buf);
if(q->buf != NULL) {
struct qbuf_metadata *metadata = (struct qbuf_metadata *)q->ptr;
/* Neighbor and packet successfully allocated */
if(packetbuf_attr(buf, PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS) == 0) {
/* Use default configuration for max transmissions */
metadata->max_transmissions = CSMA_MAX_MAC_TRANSMISSIONS;
} else {
metadata->max_transmissions =
packetbuf_attr(buf, PACKETBUF_ATTR_MAX_MAC_TRANSMISSIONS);
}
metadata->sent = sent;
metadata->cptr = ptr;
if(packetbuf_attr(buf, PACKETBUF_ATTR_PACKET_TYPE) ==
PACKETBUF_ATTR_PACKET_TYPE_ACK) {
list_push(n->queued_packet_list, q);
} else {
list_add(n->queued_packet_list, q);
}
PRINTF("csma: send_packet, queue length %d, free packets %d\n",
list_length(n->queued_packet_list), memb_numfree(&packet_memb));
/* if received packet is last fragment/only one packet start sending
* packets in list, do not start any timer.*/
if (last_fragment) {
transmit_packet_list(buf, n);
}
return 1;
}
memb_free(&metadata_memb, q->ptr);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
memb_free(&packet_memb, q);
PRINTF("csma: could not allocate queuebuf, dropping packet\n");
}
/* The packet allocation failed. Remove and free neighbor entry if empty. */
if(list_length(n->queued_packet_list) == 0) {
list_remove(uip_neighbor_list(buf), n);
memb_free(&neighbor_memb, n);
}
} else {
PRINTF("csma: Neighbor queue full\n");
}
PRINTF("csma: could not allocate packet, dropping packet\n");
} else {
PRINTF("csma: could not allocate neighbor, dropping packet\n");
}
mac_call_sent_callback(buf, sent, ptr, MAC_TX_ERR, 1);
return 0;
}