VRRP: Increasing Reliability and Failover with the Virtual Router Redundance Protocol

C.8. Configuring a List of IP Addresses for a Virtual Router

/*********************************************************
 NAME : cfg_add_ipaddr
*********************************************************/
static void cfg_add_ipaddr( vrrp_rt *vsrv, uint32_t ipaddr )
{
   vsrv->naddr++;
   /* alloc the room */
   if( vsrv->vaddr ){
         vsrv->vaddr = realloc( vsrv->vaddr
                             , vsrv->naddr*sizeof(*vsrv-
                               >vaddr) );
   } else {
          vsrv->vaddr = malloc( sizeof(*vsrv->vaddr) );
   }
   assert( vsrv->vaddr );
   /* store the data */
   vsrv->vaddr[vsrv->naddr-1].addr        = ipaddr;
   vsrv->vaddr[vsrv->naddr-1].deletable   = 0;
}

The function cfg_add_ipaddr is called with a specific virtual router structure and one IP address to be added to the list of IP addresses for this virtual router.