/*               Kernel AODV  v2.1National Institute of Standards and Technology               Luke Klein-Berndt-----------------------------------------------------  Version 2.1 new features:     * Much more stable!     * Added locks around important areas     * Multihop Internet gatewaying now works     * Multicast hack added     * Many bug fixes!-----------------------------------------------------Originally based upon MadHoc code. I am notsure how much of it is left anymore, but MadHocproved to be a great starting point.MadHoc was written by - Fredrik Lilieblad,Oskar Mattsson, Petra Nylund, Dan Ouchterlonyand Anders Roxenhag Mail: mad-hoc@flyinglinux.netThis software is Open Source under the GNU General Public Licence.*/#include "event_queue.h"/****************************************************   event_queue----------------------------------------------------This is a queue used to store events which haveto be dealt with. They are queued instead ofbeing acted on directly because a lot of theevents are recieved on interupts and you wantto limit the amount of work being done oninterupts!****************************************************/extern u_int32_t g_broadcast_ip;struct event_queue_entry *event_queue;struct event_queue_entry *end_event_queue;spinlock_t event_lock = SPIN_LOCK_UNLOCKED;void lock_event(){  spin_lock_bh(&event_lock);}void unlock_event(){  spin_unlock_bh(&event_lock);}/****************************************************   insert_event_queue_entry----------------------------------------------------Inserts an event into the event queue. dev is thedevice the event was recieved on. data pointsto the event itself.****************************************************/int insert_event_queue_entry(int type,struct sk_buff *packet){  struct event_queue_entry *new_entry;  struct interface_list_entry *tmp_interface;  struct iphdr *ip;  int start_point=sizeof(struct udphdr)+sizeof(struct iphdr);  if ((new_entry = (struct event_queue_entry*)kmalloc(sizeof(struct event_queue_entry),GFP_ATOMIC)) == NULL)    {      printk(KERN_WARNING "AODV: Not enough memory to create Event Queue Entry\n");      return -ENOMEM;    }  new_entry->time = getcurrtime();  new_entry->type = type;  new_entry->prev = NULL;  if (type<100)    {      ip  = packet->nh.iph;      new_entry->src_ip = ip->saddr;      new_entry->dst_ip = ip->daddr;      new_entry->ttl = ip->ttl;      new_entry->dev = packet->dev;      new_entry->size = packet->len-start_point;            //create space for the data and copy it there      if ((new_entry->data = kmalloc(new_entry->size,GFP_ATOMIC)) ==  NULL)	{	  kfree(new_entry);	  printk(KERN_WARNING "AODV: Not enough memory to create Event Queue Data Entry\n");	  return -ENOMEM;	}      memcpy(new_entry->data,packet->data+start_point,new_entry->size);    }    switch (type)    {      //RREP    case EVENT_RREP:      memcpy(&(new_entry->src_hw_addr),&(packet->mac.ethernet->h_source),sizeof(unsigned char)*ETH_ALEN);      break;          default:      break;    } /*lock table*/    lock_event();    //Set all the variables  new_entry->next=event_queue;  if (event_queue==NULL)      end_event_queue=new_entry;  else      event_queue->prev=new_entry;    event_queue=new_entry;      /*unlock table*/  unlock_event();  //wake up the AODV thread  kick_aodv();    return 0;}/****************************************************   get_last_event_queue_entry----------------------------------------------------Gets the last entry from the event queue****************************************************/struct event_queue_entry *get_next_event_queue_entry( void ){  struct event_queue_entry *temp_entry=NULL;  /*lock table*/  lock_event();    if (end_event_queue!=NULL)    {      temp_entry=end_event_queue;      if (temp_entry->prev==NULL)	{	  end_event_queue=NULL;	  event_queue=NULL;	}      else	{	  end_event_queue=temp_entry->prev;	  end_event_queue->next=NULL;	}    }  /*unlock table*/  unlock_event();  return temp_entry;  }/****************************************************   init_event_queue----------------------------------------------------Initalizes the event queue****************************************************/int init_event_queue( void ){    event_queue = NULL;    end_event_queue = NULL;    return 0;}/****************************************************   cleanup_event_queue----------------------------------------------------Deletes eveything in the event queue!****************************************************/int cleanup_event_queue(void ){  struct event_queue_entry *temp_entry=NULL;  while ((temp_entry=get_next_event_queue_entry())!=NULL)    {      kfree(temp_entry->data);      kfree(temp_entry);    } return 0;}