/* 
   Unix SMB/Netbios implementation.
   Version 1.9.
   NBT netbios routines and daemon - version 2
   Copyright (C) Andrew Tridgell 1994-1998
   Copyright (C) Luke Kenneth Casson Leighton 1994-1998
   Copyright (C) Jeremy Allison 1994-1998
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   
*/

#include "includes.h"
#include "smb.h"

extern int ClientNMB;

extern int DEBUGLEVEL;

extern pstring myname;
extern fstring myworkgroup;
extern char **my_netbios_names;
extern uint16 samba_nb_type;
extern struct in_addr ipzero;

int workgroup_count = 0; /* unique index key: one for each workgroup */

/****************************************************************************
  Add a workgroup into the list.
  **************************************************************************/

static void add_workgroup(struct subnet_record *subrec, struct work_record *work)
{
  struct work_record *w2;

  work->subnet = subrec;

  if (!subrec->workgrouplist)
  {
    subrec->workgrouplist = work;
    work->prev = NULL;
    work->next = NULL;
    return;
  }
  
  for (w2 = subrec->workgrouplist; w2->next; w2 = w2->next)
    ;
  
  w2->next = work;
  work->next = NULL;
  work->prev = w2;

  subrec->work_changed = True;
}

/****************************************************************************
  Create an empty workgroup.
  **************************************************************************/

static struct work_record *create_workgroup(char *name, int ttl)
{
  struct work_record *work;
  struct subnet_record *subrec;
  int t = -1;
  
  if((work = (struct work_record *)malloc(sizeof(*work))) == NULL)
  {
    DEBUG(0,("create_workgroup: malloc fail !\n"));
    return NULL;
  }
  bzero((char *)work, sizeof(*work));
 
  StrnCpy(work->work_group,name,sizeof(work->work_group)-1);
  work->serverlist = NULL;
  
  work->RunningElection = False;
  work->ElectionCount = 0;
  work->announce_interval = 0;
  work->needelection = False;
  work->needannounce = True;
  work->lastannounce_time = time(NULL);
  work->mst_state = lp_local_master() ? MST_POTENTIAL : MST_NONE;
  work->dom_state = DOMAIN_NONE;
  work->log_state = LOGON_NONE;
  
  work->death_time = (ttl != PERMANENT_TTL) ? time(NULL)+(ttl*3) : PERMANENT_TTL;

  /* Make sure all token representations of workgroups are unique. */
  
  for (subrec = FIRST_SUBNET; subrec && (t == -1); 
           subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec))
  {
    struct work_record *w;
    for (w = subrec->workgrouplist; w && t == -1; w = w->next)
    {
      if (strequal(w->work_group, work->work_group))
        t = w->token;
    }
  }
  
  if (t == -1)
    work->token = ++workgroup_count;
  else
    work->token = t;
  
  /* No known local master browser as yet. */
  *work->local_master_browser_name = '\0';

  /* No known domain master browser as yet. */
  *work->dmb_name.name = '\0';
  putip((char *)&work->dmb_addr, &ipzero);

  /* WfWg  uses 01040b01 */
  /* Win95 uses 01041501 */
  /* NTAS  uses ???????? */
  work->ElectionCriterion  = (MAINTAIN_LIST)|(ELECTION_VERSION<<8); 
  work->ElectionCriterion |= (lp_os_level() << 24);
  if (lp_domain_master())
    work->ElectionCriterion |= 0x80;
  
  return work;
}

/*******************************************************************
  Remove a workgroup.
  ******************************************************************/

static struct work_record *remove_workgroup_from_subnet(struct subnet_record *subrec, 
                                     struct work_record *work)
{
  struct work_record *ret_work = NULL;
  
  DEBUG(3,("remove_workgroup: Removing workgroup %s\n", work->work_group));
  
  ret_work = work->next;

  remove_all_servers(work);
  
  if (!work->serverlist)
  {
    if (work->prev)
      work->prev->next = work->next;
    if (work->next)
      work->next->prev = work->prev;
  
    if (subrec->workgrouplist == work)
      subrec->workgrouplist = work->next; 
  
    free((char *)work);
  }
  
  subrec->work_changed = True;

  return ret_work;
}


/****************************************************************************
  Find a workgroup in the workgroup list of a subnet.
  **************************************************************************/

struct work_record *find_workgroup_on_subnet(struct subnet_record *subrec, 
                                             fstring name)
{
  struct work_record *ret;
  
  DEBUG(4, ("find_workgroup_on_subnet: workgroup search for %s on subnet %s: ",
            name, subrec->subnet_name));
  
  for (ret = subrec->workgrouplist; ret; ret = ret->next)
  {
    if (!strcmp(ret->work_group,name))
    {
      DEBUG(4, ("found\n"));
      return(ret);
    }
  }
  DEBUG(4, ("not found\n"));
  return NULL;
}

/****************************************************************************
  Create a workgroup in the workgroup list of the subnet.
  **************************************************************************/

struct work_record *create_workgroup_on_subnet(struct subnet_record *subrec,
                                               fstring name, int ttl)
{
  struct work_record *work = NULL;

  DEBUG(4,("create_workgroup_on_subnet: creating group %s on subnet %s\n",
           name, subrec->subnet_name));
  
  if ((work = create_workgroup(name, ttl)))
  {
    add_workgroup(subrec, work);

    subrec->work_changed = True;

    return(work);
  }

  return NULL;
}

/****************************************************************************
  Update a workgroup ttl.
  **************************************************************************/

void update_workgroup_ttl(struct work_record *work, int ttl)
{
  if(work->death_time != PERMANENT_TTL)
    work->death_time = time(NULL)+(ttl*3);
  work->subnet->work_changed = True;
}

/****************************************************************************
 Fail function called if we cannot register the WORKGROUP<0> and
 WORKGROUP<1e> names on the net.
**************************************************************************/
     
static void fail_register(struct subnet_record *subrec, struct response_record *rrec,
                          struct nmb_name *nmbname)
{  
  DEBUG(0,("fail_register: Failed to register name %s on subnet %s.\n",
            namestr(nmbname), subrec->subnet_name));
}  

/****************************************************************************
 If the workgroup is our primary workgroup, add the required names to it.
**************************************************************************/

void initiate_myworkgroup_startup(struct subnet_record *subrec, struct work_record *work)
{
  int i;

  if(!strequal(myworkgroup, work->work_group))
    return;

  /* If this is a broadcast subnet then start elections on it
     if we are so configured. */

  if ((subrec != unicast_subnet) && (subrec != remote_broadcast_subnet) &&
      (subrec != wins_server_subnet) && lp_preferred_master() &&
      lp_local_master())
  {
    DEBUG(3, ("initiate_myworkgroup_startup: preferred master startup for \
workgroup %s on subnet %s\n", work->work_group, subrec->subnet_name));
    work->needelection = True;
    work->ElectionCriterion |= (1<<3);
  }  
  
  /* Register the WORKGROUP<0> and WORKGROUP<1e> names on the network. */

  register_name(subrec,myworkgroup,0x0,samba_nb_type|NB_GROUP,
                NULL,
                fail_register,NULL);
     
  register_name(subrec,myworkgroup,0x1e,samba_nb_type|NB_GROUP,
                NULL,
                fail_register,NULL);
     
  for( i = 0; my_netbios_names[i]; i++)
  {
    char *name = my_netbios_names[i];
    int stype = lp_default_server_announce() | (lp_local_master() ?
                        SV_TYPE_POTENTIAL_BROWSER : 0 );
   
    if(!strequal(myname, name))
        stype &= ~(SV_TYPE_MASTER_BROWSER|SV_TYPE_POTENTIAL_BROWSER|
                   SV_TYPE_DOMAIN_MASTER|SV_TYPE_DOMAIN_MEMBER);
   
    create_server_on_workgroup(work,name,stype|SV_TYPE_LOCAL_LIST_ONLY,
                PERMANENT_TTL, lp_serverstring());
    DEBUG(3,("initiate_myworkgroup_startup: Added server name entry %s \
on subnet %s\n", name, subrec->subnet_name));
  }
} 

/****************************************************************************
  Dump a copy of the workgroup database into the log file.
  **************************************************************************/

void dump_workgroups(BOOL force_write)
{
  struct subnet_record *subrec;
  int debuglevel = force_write ? 0 : 4;
 
  for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec))
  {
    if (subrec->workgrouplist)
    {
      struct work_record *work;
	  
      DEBUG(debuglevel,("dump_workgroups: dump workgroup on subnet %15s: ", subrec->subnet_name));
      DEBUG(debuglevel,(" netmask=%15s:\n", inet_ntoa(subrec->mask_ip)));
	  
      for (work = subrec->workgrouplist; work; work = work->next)
      {
        DEBUG(debuglevel,("\t%s(%d) current master browser = %s\n", work->work_group, 
                  work->token, 
                  *work->local_master_browser_name ? work->local_master_browser_name : "UNKNOWN" ));
        if (work->serverlist)
        {
          struct server_record *servrec;		  
          for (servrec = work->serverlist; servrec; servrec = servrec->next)
          {
            DEBUG(debuglevel,("\t\t%s %8x (%s)\n",
                  servrec->serv.name, servrec->serv.type, servrec->serv.comment));
          }
        }
      }
    }
  }
}

/****************************************************************************
  Expire any dead servers on all workgroups. If the workgroup has expired
  remove it.
  **************************************************************************/

void expire_workgroups_and_servers(time_t t)
{
  struct subnet_record *subrec;
   
  for (subrec = FIRST_SUBNET; subrec; subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec))
  {
    struct work_record *work;
    struct work_record *nextwork;

    for (work = subrec->workgrouplist; work; work = nextwork)
    {
      nextwork = work->next;
      expire_servers(work, t);

      if ((work->serverlist == NULL) && (work->death_time != PERMANENT_TTL) && 
                     ((t == -1) || (work->death_time < t)))
      {
        DEBUG(3,("expire_workgroups_and_servers: Removing timed out workgroup %s\n",
                  work->work_group));
        remove_workgroup_from_subnet(subrec, work);
      }
    }
  }
}
