1 /* 2 * Copyright (C) 2008 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 18 /* 19 * System clock functions. 20 */ 21 22 #define LOG_TAG "SystemClock" 23 24 #include <utils/SystemClock.h> 25 26 #include <string.h> 27 #include <errno.h> 28 #include <time.h> 29 30 #include <cutils/compiler.h> 31 32 #include <utils/Timers.h> 33 #include <utils/Log.h> 34 35 namespace android { 36 37 /* 38 * native public static long uptimeMillis(); 39 */ uptimeMillis()40int64_t uptimeMillis() 41 { 42 int64_t when = systemTime(SYSTEM_TIME_MONOTONIC); 43 return (int64_t) nanoseconds_to_milliseconds(when); 44 } 45 46 /* 47 * native public static long elapsedRealtime(); 48 */ elapsedRealtime()49int64_t elapsedRealtime() 50 { 51 return nanoseconds_to_milliseconds(elapsedRealtimeNano()); 52 } 53 54 /* 55 * native public static long elapsedRealtimeNano(); 56 */ elapsedRealtimeNano()57int64_t elapsedRealtimeNano() 58 { 59 #if defined(__linux__) 60 struct timespec ts; 61 int err = clock_gettime(CLOCK_BOOTTIME, &ts); 62 if (CC_UNLIKELY(err)) { 63 // This should never happen, but just in case ... 64 ALOGE("clock_gettime(CLOCK_BOOTTIME) failed: %s", strerror(errno)); 65 return 0; 66 } 67 68 return seconds_to_nanoseconds(ts.tv_sec) + ts.tv_nsec; 69 #else 70 return systemTime(SYSTEM_TIME_MONOTONIC); 71 #endif 72 } 73 74 }; // namespace android 75