1 /*
2 * Copyright (c) 2016, The OpenThread Authors.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * 3. Neither the name of the copyright holder nor the
13 * names of its contributors may be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 /**
30 * @file
31 * This file implements common MeshCoP timestamp processing.
32 */
33
34 #include "timestamp.hpp"
35
36 #include "common/code_utils.hpp"
37 #include "common/num_utils.hpp"
38 #include "common/numeric_limits.hpp"
39
40 namespace ot {
41 namespace MeshCoP {
42
ConvertTo(Info & aInfo) const43 void Timestamp::ConvertTo(Info &aInfo) const
44 {
45 aInfo.mSeconds = GetSeconds();
46 aInfo.mTicks = GetTicks();
47 aInfo.mAuthoritative = GetAuthoritative();
48 }
49
SetFrom(const Info & aInfo)50 void Timestamp::SetFrom(const Info &aInfo)
51 {
52 SetSeconds(aInfo.mSeconds);
53 SetTicks(aInfo.mTicks);
54 SetAuthoritative(aInfo.mAuthoritative);
55 }
56
SetToInvalid(void)57 void Timestamp::SetToInvalid(void)
58 {
59 mSeconds16 = NumericLimits<uint16_t>::kMax;
60 mSeconds32 = NumericLimits<uint32_t>::kMax;
61 mTicksAndAuthFlag = NumericLimits<uint16_t>::kMax;
62 }
63
IsValid(void) const64 bool Timestamp::IsValid(void) const
65 {
66 return (mSeconds16 != NumericLimits<uint16_t>::kMax) || (mSeconds32 != NumericLimits<uint32_t>::kMax) ||
67 (mTicksAndAuthFlag != NumericLimits<uint16_t>::kMax);
68 }
69
SetToOrphanAnnounce(void)70 void Timestamp::SetToOrphanAnnounce(void)
71 {
72 mSeconds16 = 0;
73 mSeconds32 = 0;
74 SetTicksAndAuthFlag(kAuthoritativeFlag);
75 }
76
IsOrphanAnnounce(void) const77 bool Timestamp::IsOrphanAnnounce(void) const
78 {
79 return (mSeconds16 == 0) && (mSeconds32 == 0) && (GetTicksAndAuthFlag() == kAuthoritativeFlag);
80 }
81
GetSeconds(void) const82 uint64_t Timestamp::GetSeconds(void) const
83 {
84 return (static_cast<uint64_t>(BigEndian::HostSwap16(mSeconds16)) << 32) + BigEndian::HostSwap32(mSeconds32);
85 }
86
SetSeconds(uint64_t aSeconds)87 void Timestamp::SetSeconds(uint64_t aSeconds)
88 {
89 mSeconds16 = BigEndian::HostSwap16(static_cast<uint16_t>(aSeconds >> 32));
90 mSeconds32 = BigEndian::HostSwap32(static_cast<uint32_t>(aSeconds & 0xffffffff));
91 }
92
SetTicks(uint16_t aTicks)93 void Timestamp::SetTicks(uint16_t aTicks)
94 {
95 SetTicksAndAuthFlag((GetTicksAndAuthFlag() & ~kTicksMask) | ((aTicks << kTicksOffset) & kTicksMask));
96 }
97
SetAuthoritative(bool aAuthoritative)98 void Timestamp::SetAuthoritative(bool aAuthoritative)
99 {
100 SetTicksAndAuthFlag((GetTicksAndAuthFlag() & kTicksMask) | (aAuthoritative ? kAuthoritativeFlag : 0));
101 }
102
Compare(const Timestamp & aFirst,const Timestamp & aSecond)103 int Timestamp::Compare(const Timestamp &aFirst, const Timestamp &aSecond)
104 {
105 int rval;
106
107 rval = ThreeWayCompare(aFirst.IsValid(), aSecond.IsValid());
108 VerifyOrExit(rval == 0);
109
110 rval = ThreeWayCompare(aFirst.GetSeconds(), aSecond.GetSeconds());
111 VerifyOrExit(rval == 0);
112
113 rval = ThreeWayCompare(aFirst.GetTicks(), aSecond.GetTicks());
114 VerifyOrExit(rval == 0);
115
116 rval = ThreeWayCompare(aFirst.GetAuthoritative(), aSecond.GetAuthoritative());
117
118 exit:
119 return rval;
120 }
121
AdvanceRandomTicks(void)122 void Timestamp::AdvanceRandomTicks(void)
123 {
124 uint16_t ticks = GetTicks();
125
126 ticks += Random::NonCrypto::GetUint32InRange(1, kMaxTicks + 1);
127
128 if (ticks > kMaxTicks)
129 {
130 ticks -= (kMaxTicks + 1);
131 SetSeconds(GetSeconds() + 1);
132 }
133
134 SetTicks(ticks);
135 }
136
137 } // namespace MeshCoP
138 } // namespace ot
139
