src/outpacket.c

   1 /* dnsmasq is Copyright (c) 2000-2013 Simon Kelley
   2
   3    This program is free software; you can redistribute it and/or modify
   4    it under the terms of the GNU General Public License as published by
   5    the Free Software Foundation; version 2 dated June, 1991, or
   6    (at your option) version 3 dated 29 June, 2007.
   7
   8    This program is distributed in the hope that it will be useful,
   9    but WITHOUT ANY WARRANTY; without even the implied warranty of
  10    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11    GNU General Public License for more details.
  12
  13    You should have received a copy of the GNU General Public License
  14    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15 */
  16
  17
  18 #include "dnsmasq.h"
  19
  20 #ifdef HAVE_DHCP6
  21
  22 static size_t outpacket_counter;
  23
  24 void end_opt6(int container)
  25 {
  26    void *p = daemon->outpacket.iov_base + container + 2;
  27    u16 len = outpacket_counter - container - 4 ;
  28
  29    PUTSHORT(len, p);
  30 }
  31
  32 int save_counter(int newval)
  33 {
  34   int ret = outpacket_counter;
  35   if (newval != -1)
  36     outpacket_counter = newval;
  37
  38   return ret;
  39 }
  40
  41 void *expand(size_t headroom)
  42 {
  43   void *ret;
  44
  45   if (expand_buf(&daemon->outpacket, outpacket_counter + headroom))
  46     {
  47       ret = daemon->outpacket.iov_base + outpacket_counter;
  48       outpacket_counter += headroom;
  49       return ret;
  50     }
  51
  52   return NULL;
  53 }
  54
  55 int new_opt6(int opt)
  56 {
  57   int ret = outpacket_counter;
  58   void *p;
  59
  60   if ((p = expand(4)))
  61     {
  62       PUTSHORT(opt, p);
  63       PUTSHORT(0, p);
  64     }
  65
  66   return ret;
  67 }
  68
  69 void *put_opt6(void *data, size_t len)
  70 {
  71   void *p;
  72
  73   if ((p = expand(len)) && data)
  74     memcpy(p, data, len);
  75
  76   return p;
  77 }
  78
  79 void put_opt6_long(unsigned int val)
  80 {
  81   void *p;
  82
  83   if ((p = expand(4)))
  84     PUTLONG(val, p);
  85 }
  86
  87 void put_opt6_short(unsigned int val)
  88 {
  89   void *p;
  90
  91   if ((p = expand(2)))
  92     PUTSHORT(val, p);
  93 }
  94
  95 void put_opt6_char(unsigned int val)
  96 {
  97   unsigned char *p;
  98
  99   if ((p = expand(1)))
 100     *p = val;
 101 }
 102
 103 void put_opt6_string(char *s)
 104 {
 105   put_opt6(s, strlen(s));
 106 }
 107
 108 #endif