Timers.h revision d245d1d09731d6a19e8a25559d3907f54441ac3d
1/* 2 * Copyright (C) 2005 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// Timer functions. 19// 20#ifndef _LIBS_UTILS_TIMERS_H 21#define _LIBS_UTILS_TIMERS_H 22 23#include <stdint.h> 24#include <sys/types.h> 25#include <sys/time.h> 26 27// ------------------------------------------------------------------ 28// C API 29 30#ifdef __cplusplus 31extern "C" { 32#endif 33 34typedef int64_t nsecs_t; // nano-seconds 35 36static inline nsecs_t seconds_to_nanoseconds(nsecs_t secs) 37{ 38 return secs*1000000000; 39} 40 41static inline nsecs_t milliseconds_to_nanoseconds(nsecs_t secs) 42{ 43 return secs*1000000; 44} 45 46static inline nsecs_t microseconds_to_nanoseconds(nsecs_t secs) 47{ 48 return secs*1000; 49} 50 51static inline nsecs_t nanoseconds_to_seconds(nsecs_t secs) 52{ 53 return secs/1000000000; 54} 55 56static inline nsecs_t nanoseconds_to_milliseconds(nsecs_t secs) 57{ 58 return secs/1000000; 59} 60 61static inline nsecs_t nanoseconds_to_microseconds(nsecs_t secs) 62{ 63 return secs/1000; 64} 65 66static inline nsecs_t s2ns(nsecs_t v) {return seconds_to_nanoseconds(v);} 67static inline nsecs_t ms2ns(nsecs_t v) {return milliseconds_to_nanoseconds(v);} 68static inline nsecs_t us2ns(nsecs_t v) {return microseconds_to_nanoseconds(v);} 69static inline nsecs_t ns2s(nsecs_t v) {return nanoseconds_to_seconds(v);} 70static inline nsecs_t ns2ms(nsecs_t v) {return nanoseconds_to_milliseconds(v);} 71static inline nsecs_t ns2us(nsecs_t v) {return nanoseconds_to_microseconds(v);} 72 73static inline nsecs_t seconds(nsecs_t v) { return s2ns(v); } 74static inline nsecs_t milliseconds(nsecs_t v) { return ms2ns(v); } 75static inline nsecs_t microseconds(nsecs_t v) { return us2ns(v); } 76 77enum { 78 SYSTEM_TIME_REALTIME = 0, // system-wide realtime clock 79 SYSTEM_TIME_MONOTONIC = 1, // monotonic time since unspecified starting point 80 SYSTEM_TIME_PROCESS = 2, // high-resolution per-process clock 81 SYSTEM_TIME_THREAD = 3 // high-resolution per-thread clock 82}; 83 84// return the system-time according to the specified clock 85#ifdef __cplusplus 86nsecs_t systemTime(int clock = SYSTEM_TIME_MONOTONIC); 87#else 88nsecs_t systemTime(int clock); 89#endif // def __cplusplus 90 91// return the system-time according to the specified clock 92int sleepForInterval(long interval, struct timeval* pNextTick); 93 94#ifdef __cplusplus 95} // extern "C" 96#endif 97 98// ------------------------------------------------------------------ 99// C++ API 100 101#ifdef __cplusplus 102 103namespace android { 104/* 105 * Time the duration of something. 106 * 107 * Includes some timeval manipulation functions. 108 */ 109class DurationTimer { 110public: 111 DurationTimer(void) {} 112 ~DurationTimer(void) {} 113 114 // Start the timer. 115 void start(void); 116 // Stop the timer. 117 void stop(void); 118 // Get the duration in microseconds. 119 long long durationUsecs(void) const; 120 121 // Subtract two timevals. Returns the difference (ptv1-ptv2) in 122 // microseconds. 123 static long long subtractTimevals(const struct timeval* ptv1, 124 const struct timeval* ptv2); 125 126 // Add the specified amount of time to the timeval. 127 static void addToTimeval(struct timeval* ptv, long usec); 128 129private: 130 struct timeval mStartWhen; 131 struct timeval mStopWhen; 132}; 133 134}; // android 135#endif // def __cplusplus 136 137#endif // _LIBS_UTILS_TIMERS_H 138