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#include <utils/Compat.h>
28
29// ------------------------------------------------------------------
30// C API
31
32#ifdef __cplusplus
33extern "C" {
34#endif
35
36typedef int64_t nsecs_t;       // nano-seconds
37
38static CONSTEXPR inline nsecs_t seconds_to_nanoseconds(nsecs_t secs)
39{
40    return secs*1000000000;
41}
42
43static CONSTEXPR inline nsecs_t milliseconds_to_nanoseconds(nsecs_t secs)
44{
45    return secs*1000000;
46}
47
48static CONSTEXPR inline nsecs_t microseconds_to_nanoseconds(nsecs_t secs)
49{
50    return secs*1000;
51}
52
53static CONSTEXPR inline nsecs_t nanoseconds_to_seconds(nsecs_t secs)
54{
55    return secs/1000000000;
56}
57
58static CONSTEXPR inline nsecs_t nanoseconds_to_milliseconds(nsecs_t secs)
59{
60    return secs/1000000;
61}
62
63static CONSTEXPR inline nsecs_t nanoseconds_to_microseconds(nsecs_t secs)
64{
65    return secs/1000;
66}
67
68static CONSTEXPR inline nsecs_t s2ns(nsecs_t v)  {return seconds_to_nanoseconds(v);}
69static CONSTEXPR inline nsecs_t ms2ns(nsecs_t v) {return milliseconds_to_nanoseconds(v);}
70static CONSTEXPR inline nsecs_t us2ns(nsecs_t v) {return microseconds_to_nanoseconds(v);}
71static CONSTEXPR inline nsecs_t ns2s(nsecs_t v)  {return nanoseconds_to_seconds(v);}
72static CONSTEXPR inline nsecs_t ns2ms(nsecs_t v) {return nanoseconds_to_milliseconds(v);}
73static CONSTEXPR inline nsecs_t ns2us(nsecs_t v) {return nanoseconds_to_microseconds(v);}
74
75static CONSTEXPR inline nsecs_t seconds(nsecs_t v)      { return s2ns(v); }
76static CONSTEXPR inline nsecs_t milliseconds(nsecs_t v) { return ms2ns(v); }
77static CONSTEXPR inline nsecs_t microseconds(nsecs_t v) { return us2ns(v); }
78
79enum {
80    SYSTEM_TIME_REALTIME = 0,  // system-wide realtime clock
81    SYSTEM_TIME_MONOTONIC = 1, // monotonic time since unspecified starting point
82    SYSTEM_TIME_PROCESS = 2,   // high-resolution per-process clock
83    SYSTEM_TIME_THREAD = 3,    // high-resolution per-thread clock
84    SYSTEM_TIME_BOOTTIME = 4   // same as SYSTEM_TIME_MONOTONIC, but including CPU suspend time
85};
86
87// return the system-time according to the specified clock
88#ifdef __cplusplus
89nsecs_t systemTime(int clock = SYSTEM_TIME_MONOTONIC);
90#else
91nsecs_t systemTime(int clock);
92#endif // def __cplusplus
93
94/**
95 * Returns the number of milliseconds to wait between the reference time and the timeout time.
96 * If the timeout is in the past relative to the reference time, returns 0.
97 * If the timeout is more than INT_MAX milliseconds in the future relative to the reference time,
98 * such as when timeoutTime == LLONG_MAX, returns -1 to indicate an infinite timeout delay.
99 * Otherwise, returns the difference between the reference time and timeout time
100 * rounded up to the next millisecond.
101 */
102int toMillisecondTimeoutDelay(nsecs_t referenceTime, nsecs_t timeoutTime);
103
104#ifdef __cplusplus
105} // extern "C"
106#endif
107
108#endif // _LIBS_UTILS_TIMERS_H
109