1/*
2 * libjingle
3 * Copyright 2004--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_TIME_H__
29#define TALK_BASE_TIME_H__
30
31#ifndef WIN32
32#include_next <time.h>
33#endif
34
35#include "talk/base/basictypes.h"
36
37namespace talk_base {
38
39typedef uint32 TimeStamp;
40
41// Returns the current time in milliseconds.
42uint32 Time();
43
44// Approximate time when the program started.
45uint32 StartTime();
46
47// Returns a future timestamp, 'elapsed' milliseconds from now.
48uint32 TimeAfter(int32 elapsed);
49
50// Comparisons between time values, which can wrap around.
51bool TimeIsBetween(uint32 earlier, uint32 middle, uint32 later);  // Inclusive
52bool TimeIsLaterOrEqual(uint32 earlier, uint32 later);  // Inclusive
53bool TimeIsLater(uint32 earlier, uint32 later);  // Exclusive
54
55// Returns the later of two timestamps.
56inline uint32 TimeMax(uint32 ts1, uint32 ts2) {
57  return TimeIsLaterOrEqual(ts1, ts2) ? ts2 : ts1;
58}
59
60// Returns the earlier of two timestamps.
61inline uint32 TimeMin(uint32 ts1, uint32 ts2) {
62  return TimeIsLaterOrEqual(ts1, ts2) ? ts1 : ts2;
63}
64
65// Number of milliseconds that would elapse between 'earlier' and 'later'
66// timestamps.  The value is negative if 'later' occurs before 'earlier'.
67int32 TimeDiff(uint32 later, uint32 earlier);
68
69// The number of milliseconds that have elapsed since 'earlier'.
70inline int32 TimeSince(uint32 earlier) {
71  return TimeDiff(Time(), earlier);
72}
73
74// The number of milliseconds that will elapse between now and 'later'.
75inline int32 TimeUntil(uint32 later) {
76  return TimeDiff(later, Time());
77}
78
79} // namespace talk_base
80
81#endif // TALK_BASE_TIME_H__
82