int ospf_hello_timer(struct thread *thread)
{
struct ospf_interface *oi;
oi = THREAD_ARG(thread);
oi->t_hello = NULL;
if (IS_DEBUG_OSPF(ism, ISM_TIMERS))
zlog(NULL, LOG_DEBUG, "ISM[%s]: Timer (Hello timer expire)",
IF_NAME(oi));
/* Sending hello packet. */
ospf_hello_send(oi);
/* Hello timer set. */
OSPF_HELLO_TIMER_ON(oi);
return 0;
}
/* Hook function called after ospf ISM event is occured. And vty's
network command invoke this function after making interface
structure. */
static void
ism_timer_set (struct ospf_interface *oi)
{
switch (oi->state)
{
case ISM_Down:
/* First entry point of ospf interface state machine. In this state
interface parameters must be set to initial values, and timers are
reset also. */
OSPF_ISM_TIMER_OFF (oi->t_hello);
OSPF_ISM_TIMER_OFF (oi->t_wait);
OSPF_ISM_TIMER_OFF (oi->t_ls_ack);
break;
case ISM_Loopback:
/* In this state, the interface may be looped back and will be
unavailable for regular data traffic. */
OSPF_ISM_TIMER_OFF (oi->t_hello);
OSPF_ISM_TIMER_OFF (oi->t_wait);
OSPF_ISM_TIMER_OFF (oi->t_ls_ack);
break;
case ISM_Waiting:
/* The router is trying to determine the identity of DRouter and
BDRouter. The router begin to receive and send Hello Packets. */
/* send first hello immediately */
OSPF_ISM_TIMER_MSEC_ON (oi->t_hello, ospf_hello_timer, 1);
OSPF_ISM_TIMER_ON (oi->t_wait, ospf_wait_timer,
OSPF_IF_PARAM (oi, v_wait));
OSPF_ISM_TIMER_OFF (oi->t_ls_ack);
break;
case ISM_PointToPoint:
/* The interface connects to a physical Point-to-point network or
virtual link. The router attempts to form an adjacency with
neighboring router. Hello packets are also sent. */
/* send first hello immediately */
OSPF_ISM_TIMER_MSEC_ON (oi->t_hello, ospf_hello_timer, 1);
OSPF_ISM_TIMER_OFF (oi->t_wait);
OSPF_ISM_TIMER_ON (oi->t_ls_ack, ospf_ls_ack_timer, oi->v_ls_ack);
break;
case ISM_DROther:
/* The network type of the interface is broadcast or NBMA network,
and the router itself is neither Designated Router nor
Backup Designated Router. */
OSPF_HELLO_TIMER_ON (oi);
OSPF_ISM_TIMER_OFF (oi->t_wait);
OSPF_ISM_TIMER_ON (oi->t_ls_ack, ospf_ls_ack_timer, oi->v_ls_ack);
break;
case ISM_Backup:
/* The network type of the interface is broadcast os NBMA network,
and the router is Backup Designated Router. */
OSPF_HELLO_TIMER_ON (oi);
OSPF_ISM_TIMER_OFF (oi->t_wait);
OSPF_ISM_TIMER_ON (oi->t_ls_ack, ospf_ls_ack_timer, oi->v_ls_ack);
break;
case ISM_DR:
/* The network type of the interface is broadcast or NBMA network,
and the router is Designated Router. */
OSPF_HELLO_TIMER_ON (oi);
OSPF_ISM_TIMER_OFF (oi->t_wait);
OSPF_ISM_TIMER_ON (oi->t_ls_ack, ospf_ls_ack_timer, oi->v_ls_ack);
break;
}
}
