xref: /titanic_50/usr/src/lib/librstp/common/times.c (revision 888e055994b8b0dc77b98c53dd97026237caec5d)
1 /************************************************************************
2  * RSTP library - Rapid Spanning Tree (802.1t, 802.1w)
3  * Copyright (C) 2001-2003 Optical Access
4  * Author: Alex Rozin
5  *
6  * This file is part of RSTP library.
7  *
8  * RSTP library is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU Lesser General Public License as published by the
10  * Free Software Foundation; version 2.1
11  *
12  * RSTP library is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser
15  * General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public License
18  * along with RSTP library; see the file COPYING.  If not, write to the Free
19  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
20  * 02111-1307, USA.
21  **********************************************************************/
22 
23 /* "Times" API : bridgeTime, rootTimes, portTimes, designatedTimes, msgTimes */
24 
25 #include "base.h"
26 
27 int
28 STP_compare_times (IN TIMEVALUES_T *t1, IN TIMEVALUES_T *t2)
29 {
30   if (t1->MessageAge < t2->MessageAge)     return -1;
31   if (t1->MessageAge > t2->MessageAge)     return  1;
32 
33   if (t1->MaxAge < t2->MaxAge)             return -2;
34   if (t1->MaxAge > t2->MaxAge)             return  2;
35 
36   if (t1->ForwardDelay < t2->ForwardDelay) return -3;
37   if (t1->ForwardDelay > t2->ForwardDelay) return  3;
38 
39   if (t1->HelloTime < t2->HelloTime)       return -4;
40   if (t1->HelloTime > t2->HelloTime)       return  4;
41 
42   return 0;
43 }
44 
45 void
46 STP_get_times (IN BPDU_BODY_T *b, OUT TIMEVALUES_T *v)
47 {
48   /* LINTED: alignment */
49   v->MessageAge =   ntohs (*((unsigned short*) b->message_age))   >> 8;
50   /* LINTED: alignment */
51   v->MaxAge =       ntohs (*((unsigned short*) b->max_age))       >> 8;
52   /* LINTED: alignment */
53   v->ForwardDelay = ntohs (*((unsigned short*) b->forward_delay)) >> 8;
54   /* LINTED: alignment */
55   v->HelloTime =    ntohs (*((unsigned short*) b->hello_time))    >> 8;
56 }
57 
58 void
59 STP_set_times (IN TIMEVALUES_T *v, OUT BPDU_BODY_T *b)
60 {
61   unsigned short mt;
62   #define STP_SET_TIME(f, t)        \
63      mt = htons (f << 8);           \
64      (void) memcpy (t, &mt, 2);
65 
66   STP_SET_TIME(v->MessageAge,   b->message_age);
67   STP_SET_TIME(v->MaxAge,       b->max_age);
68   STP_SET_TIME(v->ForwardDelay, b->forward_delay);
69   STP_SET_TIME(v->HelloTime,    b->hello_time);
70 }
71 
72 void
73 STP_copy_times (OUT TIMEVALUES_T *t, IN TIMEVALUES_T *f)
74 {
75   t->MessageAge = f->MessageAge;
76   t->MaxAge = f->MaxAge;
77   t->ForwardDelay = f->ForwardDelay;
78   t->HelloTime = f->HelloTime;
79 }
80 
81