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 #include <time.h> 32 33 #include "talk/base/basictypes.h" 34 35 namespace talk_base { 36 37 static const int64 kNumMillisecsPerSec = INT64_C(1000); 38 static const int64 kNumMicrosecsPerSec = INT64_C(1000000); 39 static const int64 kNumNanosecsPerSec = INT64_C(1000000000); 40 41 static const int64 kNumMicrosecsPerMillisec = kNumMicrosecsPerSec / 42 kNumMillisecsPerSec; 43 static const int64 kNumNanosecsPerMillisec = kNumNanosecsPerSec / 44 kNumMillisecsPerSec; 45 46 // January 1970, in NTP milliseconds. 47 static const int64 kJan1970AsNtpMillisecs = INT64_C(2208988800000); 48 49 typedef uint32 TimeStamp; 50 51 // Returns the current time in milliseconds. 52 uint32 Time(); 53 // Returns the current time in nanoseconds. 54 uint64 TimeNanos(); 55 56 // Stores current time in *tm and microseconds in *microseconds. 57 void CurrentTmTime(struct tm *tm, int *microseconds); 58 59 // Returns a future timestamp, 'elapsed' milliseconds from now. 60 uint32 TimeAfter(int32 elapsed); 61 62 // Comparisons between time values, which can wrap around. 63 bool TimeIsBetween(uint32 earlier, uint32 middle, uint32 later); // Inclusive 64 bool TimeIsLaterOrEqual(uint32 earlier, uint32 later); // Inclusive 65 bool TimeIsLater(uint32 earlier, uint32 later); // Exclusive 66 67 // Returns the later of two timestamps. 68 inline uint32 TimeMax(uint32 ts1, uint32 ts2) { 69 return TimeIsLaterOrEqual(ts1, ts2) ? ts2 : ts1; 70 } 71 72 // Returns the earlier of two timestamps. 73 inline uint32 TimeMin(uint32 ts1, uint32 ts2) { 74 return TimeIsLaterOrEqual(ts1, ts2) ? ts1 : ts2; 75 } 76 77 // Number of milliseconds that would elapse between 'earlier' and 'later' 78 // timestamps. The value is negative if 'later' occurs before 'earlier'. 79 int32 TimeDiff(uint32 later, uint32 earlier); 80 81 // The number of milliseconds that have elapsed since 'earlier'. 82 inline int32 TimeSince(uint32 earlier) { 83 return TimeDiff(Time(), earlier); 84 } 85 86 // The number of milliseconds that will elapse between now and 'later'. 87 inline int32 TimeUntil(uint32 later) { 88 return TimeDiff(later, Time()); 89 } 90 91 // Converts a unix timestamp in nanoseconds to an NTP timestamp in ms. 92 inline int64 UnixTimestampNanosecsToNtpMillisecs(int64 unix_ts_ns) { 93 return unix_ts_ns / kNumNanosecsPerMillisec + kJan1970AsNtpMillisecs; 94 } 95 96 } // namespace talk_base 97 98 #endif // TALK_BASE_TIMEUTILS_H_ 99