void mac_data_req(mac_data_req_t *req)
{
mac_hdr_t hdr;
bool indirect;
memset(&hdr, 0, sizeof(mac_hdr_t));
hdr.mac_frm_ctrl.frame_type = MAC_DATA;
hdr.mac_frm_ctrl.ack_req = (bool)(req->tx_options & MAC_ACK_REQUEST);
hdr.mac_frm_ctrl.frame_ver = MAC_802_15_4_2006;
hdr.dsn = pib.dsn++;
hdr.dest_pan_id = req->dest_pan_id;
hdr.src_pan_id = req->src_pan_id;
memcpy(&hdr.src_addr, &req->src_addr, sizeof(address_t));
memcpy(&hdr.dest_addr, &req->dest_addr, sizeof(address_t));
// generate the header
mac_gen_header(req->buf, &hdr);
DBG_PRINT_RAW("\n<OUTGOING>\n");
debug_dump_mac_hdr(&hdr);
// send the frame to the tx handler for processing
indirect = (req->tx_options & MAC_INDIRECT_TRANS);
mac_tx_handler(req->buf, &hdr.dest_addr, indirect, hdr.mac_frm_ctrl.ack_req, hdr.dsn, req->msdu_handle);
}
/*
* Handle the rx events from the mac process. If the driver
* receives a valid frame, it will send an event to the mac
* process. The mac process will then call the event handler
* which retrieves the frame from the rx queue and parses it.
* Once parsed, it will be handled according to the frame type.
* If its a command frame, it gets sent to the command handler,
* a data frame gets sent to the next higher layer, etc...
*/
static void mac_eventhandler(process_event_t event)
{
buffer_t *buf, *buf_out;
mac_hdr_t hdr;
mac_cmd_t cmd;
bool frm_pend;
mac_pcb_t *pcb = mac_pcb_get();
mac_pib_t *pib = mac_pib_get();
if (event == event_mac_rx)
{
DBG_PRINT("MAC_EVENTHANDLER: Rx event occurred.\n");
buf = mac_queue_buf_pop();
if (buf) {
DBG_PRINT_RAW("\n<INCOMING>");
debug_dump_buf(buf->dptr, buf->len);
/* decode the packet */
mac_parse_hdr(buf, &hdr);
debug_dump_mac_hdr(&hdr);
/*
* check if an ack is needed. if so, then generate
* an ack and queue it for transmission. the frm
* pending bit will be set for any frame coming from
* an address that has an indirect frame for it. this
* is against the spec, but it will speed up the ack
* transmission.
* NOTE: the ack response section may change due to the
* tight ack timing requirements.
*/
if (hdr.mac_frm_ctrl.ack_req)
{
BUF_ALLOC(buf_out, TX);
DBG_PRINT("MAC: ACK Required.\n");
frm_pend = mac_indir_frm_pend(&hdr.src_addr);
mac_gen_ack(buf_out, frm_pend, hdr.dsn);
mac_out(buf_out, false, hdr.dsn, 0);
}
/*
* process accordingly. if a scan is in progress,
* all frames except for beacon frames will be
* discarded.
*/
switch(hdr.mac_frm_ctrl.frame_type)
{
case MAC_COMMAND:
if (pcb->mac_state != MLME_SCAN)
{
/*
* need to handle the case that this is an indirect
* transfer, which means that we need to stop the
* poll timer and send a status to the poll confirm.
*/
if ((pcb->mac_state == MLME_DATA_REQ) &&
(hdr.src_addr.mode == SHORT_ADDR) &&
(hdr.src_addr.short_addr == pib->coord_addr.short_addr))
{
ctimer_stop(&pcb->mlme_tmr);
mac_poll_conf(MAC_SUCCESS);
}
mac_parse_cmd(buf, &cmd);
mac_cmd_handler(&cmd, &hdr);
}
buf_free(buf);
break;
case MAC_BEACON:
/* discard the beacon if we're not doing a scan */
if (pcb->mac_state == MLME_SCAN)
{
mac_parse_beacon(buf, &hdr);
mac_beacon_notify_ind(buf, mac_scan_descr_find_addr(&hdr.src_addr));
}
buf_free(buf);
break;
case MAC_ACK:
mac_retry_ack_handler(hdr.dsn);
/*
* we need to do some special ops depending on the
* state we're in if we get an ACK.
*/
if (pcb->mac_state == MLME_ASSOC_REQ)
{
if (pcb->assoc_req_dsn == hdr.dsn)
ctimer_set(&pcb->mlme_tmr,
pib->resp_wait_time,
mac_poll_req,
NULL);
} else if (pcb->mac_state == MLME_DATA_REQ) {
if (hdr.mac_frm_ctrl.frame_pending)
ctimer_set(&pcb->mlme_tmr,
aMacMaxFrameTotalWaitTime,
mac_poll_timeout,
NULL);
}
buf_free(buf);
break;
case MAC_DATA:
if (pcb->mac_state != MLME_SCAN)
{
/*
* need to handle the case that this is an indirect
* transfer, which means that we need to stop the poll
* timer and send a status to the poll confirm.
*/
if ((pcb->mac_state == MLME_DATA_REQ) &&
(hdr.src_addr.mode == SHORT_ADDR) &&
(hdr.src_addr.short_addr == pib->coord_addr.short_addr))
{
ctimer_stop(&pcb->mlme_tmr);
mac_poll_conf(MAC_SUCCESS);
}
mac_data_ind(buf, &hdr);
} else
buf_free(buf);
break;
default:
/* TODO: Add a statistic here to capture an error'd rx */
break;
}
}
/*
* there's a possibility that more than one frame is in the
* buffer. if they came in before this function gets executed.
* So process until the queue is empty.
*/
if (!mac_queue_is_empty())
{
while (process_post(&mac_process, event_mac_rx, NULL) != PROCESS_ERR_OK)
{
;
}
}
}
}
