1 /* 2 * Copyright (c) 2020, 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 includes definitions for a time ticker. 32 */ 33 34 #ifndef TIME_TICKER_HPP_ 35 #define TIME_TICKER_HPP_ 36 37 #include "openthread-core-config.h" 38 39 #include <limits.h> 40 41 #include "common/locator.hpp" 42 #include "common/non_copyable.hpp" 43 #include "common/time.hpp" 44 #include "common/timer.hpp" 45 46 namespace ot { 47 48 /** 49 * This class represents a time ticker. 50 * 51 * The time ticker emits periodic ticks (with 1 second period interval) to a set of registered tick receiver modules. 52 * The tick receivers (OpenThread objects) are identified by the `Receiver` enumeration. The receiver objects 53 * must provide `HandleTimeTick()` method which would be invoked by `TimeTicker` periodically. 54 * 55 */ 56 class TimeTicker : public InstanceLocator, private NonCopyable 57 { 58 public: 59 /** 60 * This enumeration represents time tick receivers. 61 * 62 * This enumeration contains the list of all OpenThread modules that can be registered as time tick receivers. 63 * 64 */ 65 enum Receiver : uint8_t 66 { 67 kMeshForwarder, ///< `MeshForwarder` 68 kMleRouter, ///< `Mle::MleRouter` 69 kAddressResolver, ///< `AddressResolver` 70 kChildSupervisor, ///< `Utils::ChildSupervisor` 71 kIp6FragmentReassembler, ///< `Ip6::Ip6` (handling of fragmented messages) 72 kDuaManager, ///< `DuaManager` 73 kMlrManager, ///< `MlrManager` 74 kNetworkDataNotifier, ///< `NetworkData::Notifier` 75 76 kNumReceivers, ///< Number of receivers. 77 }; 78 79 /** 80 * This constructor initializes the `TimeTicker` instance. 81 * 82 */ 83 explicit TimeTicker(Instance &aInstance); 84 85 /** 86 * This method registers a receiver with `TimeTicker` to receive periodic ticks. 87 * 88 * @param[in] aReceiver A tick receiver identifier. 89 * 90 */ 91 void RegisterReceiver(Receiver aReceiver); 92 93 /** 94 * This method unregisters a receiver with `TimeTicker` to receive periodic ticks. 95 * 96 * @param[in] aReceiver A tick receiver identifier. 97 * 98 */ 99 void UnregisterReceiver(Receiver aReceiver); 100 101 /** 102 * This method indicates whether a receiver is registered with `TimeTicker` to receive periodic ticks. 103 * 104 * @param[in] aReceiver A tick receiver identifier. 105 * 106 * @retval TRUE If @p aReceiver is registered with `TimeTicker`. 107 * @retval FALSE If @p aReceiver is not registered with `TimeTicker`. 108 * 109 */ IsReceiverRegistered(Receiver aReceiver) const110 bool IsReceiverRegistered(Receiver aReceiver) const { return (mReceivers & Mask(aReceiver)) != 0; } 111 112 private: 113 static constexpr uint32_t kTickInterval = Time::kOneSecondInMsec; 114 static constexpr uint32_t kRestartJitter = 4; // in msec, jitter added when restarting the timer [-4,+4] ms. 115 Mask(Receiver aReceiver)116 constexpr static uint32_t Mask(Receiver aReceiver) { return static_cast<uint32_t>(1U) << aReceiver; } 117 118 static void HandleTimer(Timer &aTimer); 119 void HandleTimer(void); 120 121 uint32_t mReceivers; 122 TimerMilli mTimer; 123 124 static_assert(kNumReceivers < sizeof(mReceivers) * CHAR_BIT, "Too many `Receiver`s - does not fit in a bit mask"); 125 }; 126 127 } // namespace ot 128 129 #endif // TIMER_HPP_ 130