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 OBOE_AUDIO_CLOCK_H 18 #define OBOE_AUDIO_CLOCK_H 19 20 #include <sys/types.h> 21 #include <ctime> 22 #include "oboe/Definitions.h" 23 24 namespace oboe { 25 26 // TODO: Move this class into the public headers because it is useful when calculating stream latency 27 class AudioClock { 28 public: 29 static int64_t getNanoseconds(clockid_t clockId = CLOCK_MONOTONIC) { 30 struct timespec time; 31 int result = clock_gettime(clockId, &time); 32 if (result < 0) { 33 return result; 34 } 35 return (time.tv_sec * kNanosPerSecond) + time.tv_nsec; 36 } 37 38 /** 39 * Sleep until the specified time. 40 * 41 * @param nanoTime time to wake up 42 * @param clockId CLOCK_MONOTONIC is default 43 * @return 0 or a negative error, eg. -EINTR 44 */ 45 46 static int sleepUntilNanoTime(int64_t nanoTime, clockid_t clockId = CLOCK_MONOTONIC) { 47 struct timespec time; 48 time.tv_sec = nanoTime / kNanosPerSecond; 49 time.tv_nsec = nanoTime - (time.tv_sec * kNanosPerSecond); 50 return 0 - clock_nanosleep(clockId, TIMER_ABSTIME, &time, NULL); 51 } 52 53 /** 54 * Sleep for the specified number of nanoseconds in real-time. 55 * Return immediately with 0 if a negative nanoseconds is specified. 56 * 57 * @param nanoseconds time to sleep 58 * @param clockId CLOCK_REALTIME is default 59 * @return 0 or a negative error, eg. -EINTR 60 */ 61 62 static int sleepForNanos(int64_t nanoseconds, clockid_t clockId = CLOCK_REALTIME) { 63 if (nanoseconds > 0) { 64 struct timespec time; 65 time.tv_sec = nanoseconds / kNanosPerSecond; 66 time.tv_nsec = nanoseconds - (time.tv_sec * kNanosPerSecond); 67 return 0 - clock_nanosleep(clockId, 0, &time, NULL); 68 } 69 return 0; 70 } 71 }; 72 73 } // namespace oboe 74 75 #endif //OBOE_AUDIO_CLOCK_H 76