1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef TIME_H_ 18 19 #define TIME_H_ 20 21 #include <stdio.h> 22 #include <stdint.h> 23 #include <stdbool.h> 24 25 #ifdef __cplusplus 26 extern "C" { 27 #endif 28 29 #define NUM_TIME_SYNC_DATAPOINTS 16 30 31 typedef struct { 32 uint64_t time1[NUM_TIME_SYNC_DATAPOINTS]; 33 uint64_t time2[NUM_TIME_SYNC_DATAPOINTS]; 34 size_t n; 35 size_t i; 36 37 uint64_t time1_base; 38 uint64_t time2_base; 39 40 bool estimate_valid; 41 float alpha, beta; 42 43 uint8_t hold_count; 44 45 } time_sync_t; 46 47 void time_sync_reset(time_sync_t *sync); 48 bool time_sync_init(time_sync_t *sync); 49 void time_sync_truncate(time_sync_t *sync, size_t window_size); 50 bool time_sync_add(time_sync_t *sync, uint64_t time1, uint64_t time2); 51 bool time_sync_estimate_time1(time_sync_t *sync, uint64_t time2, uint64_t *time1); 52 void time_sync_hold(time_sync_t *sync, uint8_t count); 53 54 #ifdef __cplusplus 55 } 56 #endif 57 58 #endif // TIME_H_ 59