1 /* 2 * Copyright (c) 2018, 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 Thread network time synchronization service. 32 */ 33 34 #ifndef TIME_SYNC_HPP_ 35 #define TIME_SYNC_HPP_ 36 37 #include "openthread-core-config.h" 38 39 #if OPENTHREAD_CONFIG_TIME_SYNC_ENABLE 40 41 #include <openthread/network_time.h> 42 43 #include "common/as_core_type.hpp" 44 #include "common/callback.hpp" 45 #include "common/locator.hpp" 46 #include "common/message.hpp" 47 #include "common/non_copyable.hpp" 48 #include "common/notifier.hpp" 49 #include "common/timer.hpp" 50 51 namespace ot { 52 53 /** 54 * Implements OpenThread Time Synchronization Service. 55 * 56 */ 57 class TimeSync : public InstanceLocator, private NonCopyable 58 { 59 friend class ot::Notifier; 60 61 public: 62 /** 63 * Represents Network Time Status 64 * 65 */ 66 enum Status : int8_t 67 { 68 kUnsynchronized = OT_NETWORK_TIME_UNSYNCHRONIZED, ///< The device hasn't attached to a network. 69 kResyncNeeded = OT_NETWORK_TIME_RESYNC_NEEDED, ///< The device hasn’t received time sync for 2 periods. 70 kSynchronized = OT_NETWORK_TIME_SYNCHRONIZED, ///< The device network time is synchronized. 71 }; 72 73 /** 74 * Initializes the object. 75 * 76 */ 77 TimeSync(Instance &aInstance); 78 79 /** 80 * Get the Thread network time. 81 * 82 * @param[in,out] aNetworkTime The Thread network time in microseconds. 83 * 84 * @returns The time synchronization status. 85 * 86 */ 87 Status GetTime(uint64_t &aNetworkTime) const; 88 89 /** 90 * Handle the message which includes time synchronization information. 91 * 92 * @param[in] aMessage The message which includes time synchronization information. 93 * 94 */ 95 void HandleTimeSyncMessage(const Message &aMessage); 96 97 #if OPENTHREAD_FTD 98 /** 99 * Send a time synchronization message when it is required. 100 * 101 * Note: A time synchronization message is required in following cases: 102 * 1. Leader send time sync message periodically; 103 * 2. Router(except Leader) received a time sync message with newer sequence; 104 * 3. Router received a time sync message with older sequence. 105 * 106 */ 107 void ProcessTimeSync(void); 108 #endif 109 110 /** 111 * Gets the time synchronization sequence. 112 * 113 * @returns The time synchronization sequence. 114 * 115 */ GetTimeSyncSeq(void) const116 uint8_t GetTimeSyncSeq(void) const { return mTimeSyncSeq; } 117 118 /** 119 * Gets the time offset to the Thread network time. 120 * 121 * @returns The time offset to the Thread network time, in microseconds. 122 * 123 */ GetNetworkTimeOffset(void) const124 int64_t GetNetworkTimeOffset(void) const { return mNetworkTimeOffset; } 125 126 /** 127 * Set the time synchronization period. 128 * 129 * @param[in] aTimeSyncPeriod The time synchronization period, in seconds. 130 * 131 */ SetTimeSyncPeriod(uint16_t aTimeSyncPeriod)132 void SetTimeSyncPeriod(uint16_t aTimeSyncPeriod) { mTimeSyncPeriod = aTimeSyncPeriod; } 133 134 /** 135 * Get the time synchronization period. 136 * 137 * @returns The time synchronization period, in seconds. 138 * 139 */ GetTimeSyncPeriod(void) const140 uint16_t GetTimeSyncPeriod(void) const { return mTimeSyncPeriod; } 141 142 /** 143 * Set the time synchronization XTAL accuracy threshold for Router. 144 * 145 * @param[in] aXtalThreshold The XTAL accuracy threshold for Router, in PPM. 146 * 147 */ SetXtalThreshold(uint16_t aXtalThreshold)148 void SetXtalThreshold(uint16_t aXtalThreshold) { mXtalThreshold = aXtalThreshold; } 149 150 /** 151 * Get the time synchronization XTAL accuracy threshold for Router. 152 * 153 * @returns The XTAL accuracy threshold for Router, in PPM. 154 * 155 */ GetXtalThreshold(void) const156 uint16_t GetXtalThreshold(void) const { return mXtalThreshold; } 157 158 /** 159 * Set the time sync callback to be notified of a network time update. 160 * 161 * @param[in] aCallback The callback to be called when time sync is handled. 162 * @param[in] aCallbackContext The context to be passed to callback. 163 * 164 */ SetTimeSyncCallback(otNetworkTimeSyncCallbackFn aCallback,void * aCallbackContext)165 void SetTimeSyncCallback(otNetworkTimeSyncCallbackFn aCallback, void *aCallbackContext) 166 { 167 mTimeSyncCallback.Set(aCallback, aCallbackContext); 168 } 169 170 /** 171 * Callback to be called when timer expires. 172 * 173 */ 174 void HandleTimeout(void); 175 176 private: 177 /** 178 * Callback to be called when thread state changes. 179 * 180 * @param[in] aFlags Flags that denote the state change events. 181 * 182 */ 183 void HandleNotifierEvents(Events aEvents); 184 185 /** 186 * Check and handle any status change, and notify observers if applicable. 187 * 188 * @param[in] aNotifyTimeUpdated True to denote that observers should be notified due to a time change, false 189 * otherwise. 190 * 191 */ 192 void CheckAndHandleChanges(bool aNotifyTimeUpdated); 193 194 /** 195 * Increase the time synchronization sequence. 196 * 197 */ 198 void IncrementTimeSyncSeq(void); 199 200 /** 201 * Notify any listener of a network time sync update event. 202 * 203 */ 204 void NotifyTimeSyncCallback(void); 205 206 using SyncTimer = TimerMilliIn<TimeSync, &TimeSync::HandleTimeout>; 207 208 bool mTimeSyncRequired; ///< Indicate whether or not a time synchronization message is required. 209 uint8_t mTimeSyncSeq; ///< The time synchronization sequence. 210 uint16_t mTimeSyncPeriod; ///< The time synchronization period. 211 uint16_t mXtalThreshold; ///< The XTAL accuracy threshold for a device to become a Router, in PPM. 212 #if OPENTHREAD_FTD 213 TimeMilli mLastTimeSyncSent; ///< The time when the last time synchronization message was sent. 214 #endif 215 TimeMilli mLastTimeSyncReceived; ///< The time when the last time synchronization message was received. 216 int64_t mNetworkTimeOffset; ///< The time offset to the Thread Network time 217 218 Callback<otNetworkTimeSyncCallbackFn> mTimeSyncCallback; ///< Callback when time sync is handled or status updated. 219 SyncTimer mTimer; ///< Timer for checking if a resync is required. 220 Status mCurrentStatus; ///< Current network time status. 221 }; 222 223 DefineMapEnum(otNetworkTimeStatus, TimeSync::Status); 224 225 /** 226 * @} 227 */ 228 229 } // namespace ot 230 231 #endif // OPENTHREAD_CONFIG_TIME_SYNC_ENABLE 232 233 #endif // TIME_SYNC_HPP_ 234