isisd/isis_flags.c

   1 /*
   2  * IS-IS Rout(e)ing protocol - isis_flags.c
   3  *                             Routines for manipulation of SSN and SRM flags
   4  *
   5  * Copyright (C) 2001,2002   Sampo Saaristo
   6  *                           Tampere University of Technology
   7  *                           Institute of Communications Engineering
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public Licenseas published by the Free
  11  * Software Foundation; either version 2 of the License, or (at your option)
  12  * any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,but WITHOUT
  15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  17  * more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; see the file COPYING; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  22  */
  23
  24 #include <zebra.h>
  25 #include "log.h"
  26 #include "linklist.h"
  27
  28 #include "isisd/isis_constants.h"
  29 #include "isisd/isis_common.h"
  30 #include "isisd/isis_flags.h"
  31
  32 void
  33 flags_initialize (struct flags *flags)
  34 {
  35   flags->maxindex = 0;
  36   flags->free_idcs = NULL;
  37 }
  38
  39 long int
  40 flags_get_index (struct flags *flags)
  41 {
  42   struct listnode *node;
  43   long int index;
  44
  45   if (flags->free_idcs == NULL || flags->free_idcs->count == 0)
  46     {
  47       index = flags->maxindex++;
  48     }
  49   else
  50     {
  51       node = listhead (flags->free_idcs);
  52       index = (long int) listgetdata (node);
  53       listnode_delete (flags->free_idcs, (void *) index);
  54       index--;
  55     }
  56
  57   return index;
  58 }
  59
  60 void
  61 flags_free_index (struct flags *flags, long int index)
  62 {
  63   if (index + 1 == flags->maxindex)
  64     {
  65       flags->maxindex--;
  66       return;
  67     }
  68
  69   if (flags->free_idcs == NULL)
  70     {
  71       flags->free_idcs = list_new ();
  72     }
  73
  74   listnode_add (flags->free_idcs, (void *) (index + 1));
  75
  76   return;
  77 }
  78
  79 int
  80 flags_any_set (u_int32_t * flags)
  81 {
  82   u_int32_t zero[ISIS_MAX_CIRCUITS];
  83   memset (zero, 0x00, ISIS_MAX_CIRCUITS * 4);
  84
  85   return bcmp (flags, zero, ISIS_MAX_CIRCUITS * 4);
  86 }