1 /*
2 * libjingle
3 * Copyright 2005 Google Inc.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice,
9 * this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation
12 * and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
19 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #ifndef TALK_BASE_TIMEUTILS_H_
29 #define TALK_BASE_TIMEUTILS_H_
30
31 #ifndef WIN32
32 #include <time.h>
33 #endif
34
35 #include "talk/base/basictypes.h"
36
37 namespace talk_base {
38
39 static const int64 kNumMillisecsPerSec = 1000;
40 static const int64 kNumMicrosecsPerSec = 1000000;
41 static const int64 kNumNanosecsPerSec = 1000000000;
42
43 static const int64 kNumMicrosecsPerMillisec = kNumMicrosecsPerSec /
44 kNumMillisecsPerSec;
45 static const int64 kNumNanosecsPerMillisec = kNumNanosecsPerSec /
46 kNumMillisecsPerSec;
47
48 typedef uint32 TimeStamp;
49
50 // Returns the current time in milliseconds.
51 uint32 Time();
52 // Returns the current time in nanoseconds.
53 uint64 TimeNanos();
54
55 // Returns a future timestamp, 'elapsed' milliseconds from now.
56 uint32 TimeAfter(int32 elapsed);
57
58 // Comparisons between time values, which can wrap around.
59 bool TimeIsBetween(uint32 earlier, uint32 middle, uint32 later); // Inclusive
60 bool TimeIsLaterOrEqual(uint32 earlier, uint32 later); // Inclusive
61 bool TimeIsLater(uint32 earlier, uint32 later); // Exclusive
62
63 // Returns the later of two timestamps.
TimeMax(uint32 ts1,uint32 ts2)64 inline uint32 TimeMax(uint32 ts1, uint32 ts2) {
65 return TimeIsLaterOrEqual(ts1, ts2) ? ts2 : ts1;
66 }
67
68 // Returns the earlier of two timestamps.
TimeMin(uint32 ts1,uint32 ts2)69 inline uint32 TimeMin(uint32 ts1, uint32 ts2) {
70 return TimeIsLaterOrEqual(ts1, ts2) ? ts1 : ts2;
71 }
72
73 // Number of milliseconds that would elapse between 'earlier' and 'later'
74 // timestamps. The value is negative if 'later' occurs before 'earlier'.
75 int32 TimeDiff(uint32 later, uint32 earlier);
76
77 // The number of milliseconds that have elapsed since 'earlier'.
TimeSince(uint32 earlier)78 inline int32 TimeSince(uint32 earlier) {
79 return TimeDiff(Time(), earlier);
80 }
81
82 // The number of milliseconds that will elapse between now and 'later'.
TimeUntil(uint32 later)83 inline int32 TimeUntil(uint32 later) {
84 return TimeDiff(later, Time());
85 }
86
87 } // namespace talk_base
88
89 #endif // TALK_BASE_TIMEUTILS_H_
90