/* dnsmasq is Copyright (c) 2000-2026 Simon Kelley

   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; version 2 dated June, 1991, or

   (at your option) version 3 dated 29 June, 2007.

   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, see <http://www.gnu.org/licenses/>.

*/

#include "dnsmasq.h"

#ifdef HAVE_DHCP6

static size_t outpacket_counter;

void end_opt6(int container)

{

   uint8_t *p = (uint8_t *)daemon->outpacket.iov_base + container + 2;

   u16 len = outpacket_counter - container - 4 ;

   PUTSHORT(len, p);

}

void reset_counter(void)

{

  /* Clear out buffer when starting from beginning */

  if (daemon->outpacket.iov_base)

    memset(daemon->outpacket.iov_base, 0, daemon->outpacket.iov_len);

  save_counter(0);

}

int save_counter(int newval)

{

  int ret = outpacket_counter;

  if (newval != -1)

    outpacket_counter = newval;

  return ret;

}

void *expand(size_t headroom)

{

  uint8_t *ret;

  if (expand_buf(&daemon->outpacket, outpacket_counter + headroom))

    {

      ret = (uint8_t *)daemon->outpacket.iov_base + outpacket_counter;

      outpacket_counter += headroom;

      return ret;

    }

  return NULL;

}

int new_opt6(int opt)

{

  int ret = outpacket_counter;

  unsigned char *p;

  if ((p = expand(4)))

    {

      PUTSHORT(opt, p);

      PUTSHORT(0, p);

    }

  return ret;

}

void *put_opt6(void *data, size_t len)

{

  void *p;

  if ((p = expand(len)) && data)

    memcpy(p, data, len);   

  return p;

}

void put_opt6_long(unsigned int val)

{

  unsigned char *p;

  if ((p = expand(4)))  

    PUTLONG(val, p);

}

void put_opt6_short(unsigned int val)

{

  uint8_t *p;

  if ((p = expand(2)))

    PUTSHORT(val, p);   

}

void put_opt6_char(unsigned int val)

{

  unsigned char *p;

  if ((p = expand(1)))

    *p = val;   

}

void put_opt6_string(char *s)

{

  put_opt6(s, strlen(s));

}

#endif