void Casan::send_discover (Msg &out)
{
char tmpstr [CASAN_BUF_LEN] ;
l2addr *dest ;
DBGLN1 (F ("Sending Discover")) ;
out.reset () ;
out.set_id (curid_++) ;
out.set_type (COAP_TYPE_NON) ;
out.set_code (COAP_CODE_POST) ;
mk_ctl_msg (out) ;
snprintf (tmpstr, sizeof tmpstr, CASAN_DISCOVER_SLAVEID, slaveid_) ;
option o1 (option::MO_Uri_Query, tmpstr, strlen (tmpstr)) ;
out.push_option (o1) ;
snprintf (tmpstr, sizeof tmpstr, CASAN_DISCOVER_MTU, (long int) defmtu_) ;
option o2 (option::MO_Uri_Query, tmpstr, strlen (tmpstr)) ;
out.push_option (o2) ;
dest = (master_ != NULL) ? master_ : l2_->bcastaddr () ;
out.send (*dest) ;
}
void Casan::check_observed_resources (Msg &out)
{
Resource *res ;
reslist *rl ;
for (rl = reslist_ ; rl != NULL ; rl = rl->next)
{
res = rl->res ;
if (res->check_trigger ())
{
DBG1 (F (B_BLUE "Observed resource '")) ;
DBG1 (rl->res->name ()) ;
DBG1 (F ("' triggered" C_RESET)) ;
DBGLN0 () ;
out.reset () ;
out.set_type (COAP_TYPE_ACK) ;
out.set_token (res->get_token ()) ;
out.set_id (curid_++) ;
out.set_code (COAP_CODE_OK) ;
option obs (option::MO_Observe, res->next_serial ()) ;
out.push_option (obs) ;
request_resource (NULL, &out, res) ;
out.send (*master_) ;
}
}
}
void Casan::send_assoc_answer (Msg &in, Msg &out)
{
l2addr *dest ;
dest = l2_->get_src () ;
// send back an acknowledgement message
out.set_type (COAP_TYPE_ACK) ;
out.set_code (COAP_CODE_OK) ;
out.set_id (in.get_id ()) ;
// will get the resources and set them in the payload in the right format
(void) get_well_known (out) ;
// send the packet
if (! out.send (*dest))
DBGLN1 (F (RED ("Cannot send the assoc answer message"))) ;
delete dest ;
}
void Casan::loop ()
{
Msg in (l2_) ;
Msg out (l2_) ;
l2net::l2_recv_t ret ;
uint8_t oldstatus ;
long int hlid ;
l2addr *srcaddr ;
int mtu ; // mtu announced by master in assoc msg
oldstatus = status_ ; // keep old value for debug display
sync_time (curtime) ; // get current time
retrans_.loop (*l2_, curtime) ; // check needed retransmissions
srcaddr = NULL ;
ret = in.recv () ; // get received message
if (ret == l2net::RECV_OK)
srcaddr = l2_->get_src () ; // get a new address
switch (status_)
{
case SL_COLDSTART :
send_discover (out) ;
twait_.init (curtime) ;
status_ = SL_WAITING_UNKNOWN ;
break ;
case SL_WAITING_UNKNOWN :
if (ret == l2net::RECV_OK)
{
retrans_.check_msg_received (in) ;
if (is_ctl_msg (in))
{
if (is_hello (in, hlid))
{
DBGLN1 (F ("Received a CTL HELLO msg")) ;
change_master (hlid, -1) ; // don't change mtu
twait_.init (curtime) ;
status_ = SL_WAITING_KNOWN ;
}
else if (is_assoc (in, sttl_, mtu))
{
DBGLN1 (F ("Received a CTL ASSOC msg")) ;
change_master (-1, mtu) ; // "unknown" hlid
send_assoc_answer (in, out) ;
trenew_.init (curtime, sttl_) ;
status_ = SL_RUNNING ;
}
else DBGLN1 (F (RED ("Unkwnon CTL"))) ;
}
}
if (status_ == SL_WAITING_UNKNOWN && twait_.next (curtime))
send_discover (out) ;
break ;
case SL_WAITING_KNOWN :
if (ret == l2net::RECV_OK)
{
retrans_.check_msg_received (in) ;
if (is_ctl_msg (in))
{
if (is_hello (in, hlid))
{
DBGLN1 (F ("Received a CTL HELLO msg")) ;
change_master (hlid, -1) ; // don't change mtu
}
else if (is_assoc (in, sttl_, mtu))
{
DBGLN1 (F ("Received a CTL ASSOC msg")) ;
change_master (-1, mtu) ; // unknown hlid
send_assoc_answer (in, out) ;
trenew_.init (curtime, sttl_) ;
status_ = SL_RUNNING ;
}
else DBGLN1 (F (RED ("Unkwnon CTL"))) ;
}
}
if (status_ == SL_WAITING_KNOWN)
{
if (twait_.expired (curtime))
{
reset_master () ; // master_ is no longer known
send_discover (out) ;
twait_.init (curtime) ; // reset timer
status_ = SL_WAITING_UNKNOWN ;
}
else if (twait_.next (curtime))
{
send_discover (out) ;
}
}
break ;
case SL_RUNNING :
case SL_RENEW :
if (ret == l2net::RECV_OK)
{
retrans_.check_msg_received (in) ;
if (is_ctl_msg (in))
{
if (is_hello (in, hlid))
{
DBGLN1 (F ("Received a CTL HELLO msg")) ;
if (! same_master (srcaddr) || hlid != hlid_)
{
int oldhlid = hlid_ ;
change_master (hlid, 0) ; // reset mtu
if (oldhlid != -1)
{
twait_.init (curtime) ;
status_ = SL_WAITING_KNOWN ;
}
}
}
else if (is_assoc (in, sttl_, mtu))
{
DBGLN1 (F ("Received a CTL ASSOC msg")) ;
if (same_master (srcaddr))
{
negociate_mtu (mtu) ;
send_assoc_answer (in, out) ;
trenew_.init (curtime, sttl_) ;
status_ = SL_RUNNING ;
}
}
else DBGLN1 (F (RED ("Unkwnon CTL"))) ;
}
else // request for a normal resource
{
// deduplicate () ;
process_request (in, out) ;
out.send (*master_) ;
}
}
else if (ret == l2net::RECV_TRUNCATED)
{
DBGLN1 (F (RED ("Request too large"))) ;
out.set_type (COAP_TYPE_ACK) ;
out.set_id (in.get_id ()) ;
out.set_token (in.get_token ()) ;
option o (option::MO_Size1, l2_->mtu ()) ;
out.push_option (o) ;
out.set_code (COAP_CODE_TOO_LARGE) ;
out.send (*master_) ;
}
check_observed_resources (out) ;
if (status_ == SL_RUNNING && trenew_.renew (curtime))
{
send_discover (out) ;
status_ = SL_RENEW ;
}
if (status_ == SL_RENEW && trenew_.next (curtime))
{
send_discover (out) ;
}
if (status_ == SL_RENEW && trenew_.expired (curtime))
{
reset_master () ; // master_ is no longer known
send_discover (out) ;
twait_.init (curtime) ; // reset timer
status_ = SL_WAITING_UNKNOWN ;
}
break ;
default :
DBGLN1 (F ("Error : casan status not known")) ;
DBGLN1 (status_) ;
break ;
}
if (oldstatus != status_)
{
DBG1 (F ("Status: " C_GREEN)) ;
print_status (oldstatus) ;
DBG1 (F (C_RESET " -> " C_GREEN)) ;
print_status (status_) ;
DBGLN1 (F (C_RESET)) ;
}
if (srcaddr != NULL)
delete srcaddr ;
}