henrike@webrtc.org | 47be73b | 2014-05-13 18:00:26 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2005 The WebRTC Project Authors. All rights reserved. |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license |
| 5 | * that can be found in the LICENSE file in the root of the source |
| 6 | * tree. An additional intellectual property rights grant can be found |
| 7 | * in the file PATENTS. All contributing project authors may |
| 8 | * be found in the AUTHORS file in the root of the source tree. |
| 9 | */ |
| 10 | |
| 11 | #ifndef WEBRTC_BASE_TIMEUTILS_H_ |
| 12 | #define WEBRTC_BASE_TIMEUTILS_H_ |
| 13 | |
| 14 | #include <time.h> |
| 15 | |
| 16 | #include "webrtc/base/basictypes.h" |
| 17 | |
| 18 | namespace rtc { |
| 19 | |
| 20 | static const int64 kNumMillisecsPerSec = INT64_C(1000); |
| 21 | static const int64 kNumMicrosecsPerSec = INT64_C(1000000); |
| 22 | static const int64 kNumNanosecsPerSec = INT64_C(1000000000); |
| 23 | |
| 24 | static const int64 kNumMicrosecsPerMillisec = kNumMicrosecsPerSec / |
| 25 | kNumMillisecsPerSec; |
| 26 | static const int64 kNumNanosecsPerMillisec = kNumNanosecsPerSec / |
| 27 | kNumMillisecsPerSec; |
| 28 | static const int64 kNumNanosecsPerMicrosec = kNumNanosecsPerSec / |
| 29 | kNumMicrosecsPerSec; |
| 30 | |
| 31 | // January 1970, in NTP milliseconds. |
| 32 | static const int64 kJan1970AsNtpMillisecs = INT64_C(2208988800000); |
| 33 | |
| 34 | typedef uint32 TimeStamp; |
| 35 | |
| 36 | // Returns the current time in milliseconds. |
| 37 | uint32 Time(); |
| 38 | // Returns the current time in microseconds. |
| 39 | uint64 TimeMicros(); |
| 40 | // Returns the current time in nanoseconds. |
| 41 | uint64 TimeNanos(); |
| 42 | |
| 43 | // Stores current time in *tm and microseconds in *microseconds. |
| 44 | void CurrentTmTime(struct tm *tm, int *microseconds); |
| 45 | |
| 46 | // Returns a future timestamp, 'elapsed' milliseconds from now. |
| 47 | uint32 TimeAfter(int32 elapsed); |
| 48 | |
| 49 | // Comparisons between time values, which can wrap around. |
| 50 | bool TimeIsBetween(uint32 earlier, uint32 middle, uint32 later); // Inclusive |
| 51 | bool TimeIsLaterOrEqual(uint32 earlier, uint32 later); // Inclusive |
| 52 | bool TimeIsLater(uint32 earlier, uint32 later); // Exclusive |
| 53 | |
| 54 | // Returns the later of two timestamps. |
| 55 | inline uint32 TimeMax(uint32 ts1, uint32 ts2) { |
| 56 | return TimeIsLaterOrEqual(ts1, ts2) ? ts2 : ts1; |
| 57 | } |
| 58 | |
| 59 | // Returns the earlier of two timestamps. |
| 60 | inline uint32 TimeMin(uint32 ts1, uint32 ts2) { |
| 61 | return TimeIsLaterOrEqual(ts1, ts2) ? ts1 : ts2; |
| 62 | } |
| 63 | |
| 64 | // Number of milliseconds that would elapse between 'earlier' and 'later' |
| 65 | // timestamps. The value is negative if 'later' occurs before 'earlier'. |
| 66 | int32 TimeDiff(uint32 later, uint32 earlier); |
| 67 | |
| 68 | // The number of milliseconds that have elapsed since 'earlier'. |
| 69 | inline int32 TimeSince(uint32 earlier) { |
| 70 | return TimeDiff(Time(), earlier); |
| 71 | } |
| 72 | |
| 73 | // The number of milliseconds that will elapse between now and 'later'. |
| 74 | inline int32 TimeUntil(uint32 later) { |
| 75 | return TimeDiff(later, Time()); |
| 76 | } |
| 77 | |
| 78 | // Converts a unix timestamp in nanoseconds to an NTP timestamp in ms. |
| 79 | inline int64 UnixTimestampNanosecsToNtpMillisecs(int64 unix_ts_ns) { |
| 80 | return unix_ts_ns / kNumNanosecsPerMillisec + kJan1970AsNtpMillisecs; |
| 81 | } |
| 82 | |
henrike@webrtc.org | 11e96c7 | 2014-05-21 20:42:17 +0000 | [diff] [blame] | 83 | class TimestampWrapAroundHandler { |
| 84 | public: |
| 85 | TimestampWrapAroundHandler(); |
| 86 | |
| 87 | int64 Unwrap(uint32 ts); |
| 88 | |
| 89 | private: |
| 90 | uint32 last_ts_; |
| 91 | int64 num_wrap_; |
| 92 | }; |
| 93 | |
henrike@webrtc.org | 47be73b | 2014-05-13 18:00:26 +0000 | [diff] [blame] | 94 | } // namespace rtc |
| 95 | |
| 96 | #endif // WEBRTC_BASE_TIMEUTILS_H_ |