| /* |
| * Copyright (c) 2016, The OpenThread Authors. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. Neither the name of the copyright holder nor the |
| * names of its contributors may be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
| * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| * POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| /** |
| * @file |
| * This file implements common MeshCoP timestamp processing. |
| */ |
| |
| #include "timestamp.hpp" |
| |
| #include "common/code_utils.hpp" |
| |
| namespace ot { |
| namespace MeshCoP { |
| |
| int Timestamp::Compare(const Timestamp *aFirst, const Timestamp *aSecond) |
| { |
| int rval; |
| uint64_t firstSeconds; |
| uint64_t secondSeconds; |
| uint16_t firstTicks; |
| uint16_t secondTicks; |
| |
| if (aFirst == nullptr) |
| { |
| // When `aFirst` is null but `aSecond is not, we return -1, |
| // (indicate `aFirst (null) < aSecond (non-null)`). |
| ExitNow(rval = (aSecond == nullptr) ? 0 : -1); |
| } |
| |
| if (aSecond == nullptr) |
| { |
| // When `aFirst` is not null, but `aSecond` is, we return +1, |
| // (indicate `aFirst (non-null) > aSecond (null)`). |
| ExitNow(rval = 1); |
| } |
| |
| // Both are non-null. |
| |
| firstSeconds = aFirst->GetSeconds(); |
| secondSeconds = aSecond->GetSeconds(); |
| |
| if (firstSeconds != secondSeconds) |
| { |
| ExitNow(rval = (firstSeconds > secondSeconds) ? 1 : -1); |
| } |
| |
| firstTicks = aFirst->GetTicks(); |
| secondTicks = aSecond->GetTicks(); |
| |
| if (firstTicks != secondTicks) |
| { |
| ExitNow(rval = (firstTicks > secondTicks) ? 1 : -1); |
| } |
| |
| rval = 0; |
| |
| exit: |
| return rval; |
| } |
| |
| void Timestamp::AdvanceRandomTicks(void) |
| { |
| uint16_t ticks = GetTicks(); |
| |
| ticks += Random::NonCrypto::GetUint32InRange(1, kMaxRandomTicks); |
| |
| if (ticks & (kTicksMask >> kTicksOffset)) |
| { |
| SetSeconds(GetSeconds() + 1); |
| } |
| |
| SetTicks(ticks); |
| } |
| |
| } // namespace MeshCoP |
| } // namespace ot |